Shared Spell
Summary: Ace shows off a rare tickle charm—only to learn the hard way that the spell affects both caster and target. Unfortunately for him, he ends up using it on Riddle.
Switch(?)! Ace Trappola
Switch(?)! Riddle Rosehearts
Word count: 2,989
At Night Raven College, the magic rumors were not new.
They had existed for years, passed down in fragments, mentioned in half-serious conversations, and dismissed just as often as it was believed. Most students had heard of it at least once. A strange spell that forced its target into uncontrollable laughter.
But that was all it ever was to them. A rumor. Something no one could actually prove. Because knowing about the charm was common but knowing how to cast it was not.
Very few students did. Barely a fraction across the entire school. Among first-years, it was practically nonexistent. Which was exactly why the reaction was so strong.
"YOU CAN CAST A TICKLE CHARM!?!?"
The shout rang through the classroom before anyone could stop it. A student jumped out of his seat, eyes wide with disbelief. "SHHH!!" Trappola hushed, grabbing the guy's shoulder and forcing him back down just as quickly. "Keep it down!" He hissed, glancing toward the door out of instinct. "Yeah yeah, I can use it! You don’t have to yell it." And that only made things worse.
"A tickle charm?" someone leaned over from the next desk. "Wait, seriously? That thing actually exists?"
"I thought it was just a story."
"No way a first-year knows it!"
The teacher’s absence gave them just enough freedom to abandon their seats. One by one, students drifted closer, until Ace found himself surrounded with curious, staring souls trying to confirm something they had only ever heard about.
Ace blinked up at them, momentarily caught off guard. It wasn’t like he’d meant to say it out loud. Tch. If the guy next to him had just kept quiet—
But still…
Ace leaned back in his chair, letting himself relax into the attention. He was a showboy after all. He loved to do and show everyone all sorts of card or coin trick, so he was used for the crowds like this. "Well yeah," he said, tone turning confident. "Course I can."
The reaction was immediate. A wave of noise, excitement, disbelief. "That’s sickkkk!!!"
"Where did you even learn that?"
Ace shrugged. "My older brother taught me." That part came out casually. The moment the words left his mouth, something unpleasant twisted in his stomach. He remembered himself younger, pinned in place by nothing but a spell he didn’t understand yet. Laughter forced out of him until it stopped being funny.
And his brother standing nearby, completely entertained. "You’ll get it eventually. Don’t be so dramatic." His brother used to say entertainingly. Ace forced the memory down just as quickly as it surfaced. "No clue where he learned it, though," he added, brushing it off with a shrug.
And the class didn’t question it. Well, why would they? To them, it was impressive and rare. Something worth being excited about. But to Ace It was something else entirely.
–––
Six students sat scattered around the dorm lounge room, each wearing the same metal, heart-shaped collar locked around their necks.
Ace let out a low whistle as he stepped further inside. "Man, what’d you even do to deserve that?" He tapped his own neck as he spoke, an easy and almost teasing gesture. And the reactions he got were immediate. Heavy groans, annoyed looks, and one long, exhausted sigh.
"There’s a rule against playing with an eighteen-sided dice," one of them muttered. "You’re kidding." Ace quirked one brow, unable to contain an amused smirk.
"I wish I was." The student bristled as he gestured weakly toward the table. The board game was still set up exactly as it had been left. Cards untouched, pieces unmoved. And sitting slightly off to the side the die that had caused all of this. Ace snorted at the sight. "Couldn’t you just use a normal one?"
"We would if we could," another groaned, collapsing back onto the couch. "The game needs an eighteen-sided die. Now we’re stuck just staring at it."
"We were in the middle of a game before housewarden came in," someone added. "It requires that die. We can’t just replace it."
The frustration in the room was quiet, but heavy. Ace scratched the back of his head, already halfway disengaged. "Well… good luck with that one, I guess. I’ve just got some club stuff to do so—" He didn’t finish due to the hand that caught his wrist. "Ace, wait!"
Ace paused and turned slowly back to meet gazes with the collared student behind him. The expression on the student’s face had changed. It was less frustrated and more…focused. "You said something this morning," he said.
Ace felt it immediately. That same uncomfortable twist in his stomach. "What did I say?"
"About that charm! About the…tickle charm," and the room immediately shifted into dramatical silence. Postures of the students around straightened, attention sharpened. Every single person in the room looked and locked at him, at Ace.
Ace let out a short, uneasy laugh. Wow, the attention... "Yeah, I said that, but—"
"Then can you use it?" The grip on Ace's wrist loosened before clamping back again around his hand in a pleading matter. "Please, use it on Housewarden Rosehearts!!"
"wh-WHA—??" Ace sputtered, eyes wide. On housewarden?? On Riddle!? Do they wanted Ace dead?? "Hey, look man, this is...This is not how it works.." he stammered as he looked around the room hoping, seriously hoping someone would shut that idea down but no one did. "Yeah, the housewarden needs to lighten up a bit.." one of them chimed in response.
"Has anyone ever heard Rosehearts laugh at all? Like, seriously" another one added up. So there were no objections…Just a few smiles that looked a little too eager.
Ace’s stomach dropped. Because unlike them he knew this wasn’t just a harmless spell. He knew exactly how it felt and what it does. And more importantly,
He knew it didn’t only affect the target…
–––
The garden of Heartslabyul was perfectly composed, as always. White tablecloths stretched neatly across long tables, bright under the afternoon sun. The roses surrounding the area painted in neat red, each one carefully maintained. Nothing was out of place, nothing was imperfect.
At the center of it all sat Riddle Rosehearts, posture straight, expression calm as he lifted his teacup to take another measured sip. Beside him stood Cater Diamond and Trey Clover, engaged in quiet conversation, their attention only loosely on their housewarden.
The atmosphere was so meticulously sweet, so peaceful and controlled that it only made the idea EVEN worse.
Hidden behind a bush that did almost nothing to conceal him, Ace Trappola crouched low, gripping his magical pen with both hands. His fingers tense holding the pen way too tight. His earlier confidence had completely disappeared.
This was bad. This was really bad. Why'd he agree to this??
Ace swallowed, shifting slightly as he peeked through the leaves. His eyes locked onto Riddle. He didn’t want to do this. Oh, how he didn't wanted to do this right now. Not after remembering what the spell actually did.
For a second, he almost lowered his pen. Perhaps he wasn’t the only one who had come to his senses, the only one who had begun to think rationally and realized just how terrible this idea truly was. But when he glanced back, he could have groaned in despair…
A whole group, crowd of spectators, of audience had gathered at a distance. Heartslabyul students pretending to walk by, pretending to talk, pretending this was all casual when it wasn’t. They were all watching, waiting and expecting Ace to do his thing.
Ace’s face flushed slightly. It's too late to back now. "...this is so stupid," he muttered under his breath. He turned back towards the garden quickly, before he could think about it too much. Riddle was still there, calm, oblivious, unaware. Ace inhaled, then raised the pen with both hands, aiming carefully. "Just—quick. Do it quick," he whispered to himself.
The spell slipped out under his breath and a faint pink glow flickered at the tip of the pen. Aaaandd nothing happened. Ace blinked. "…Did it even—"
Riddle twitched suddenly. Riddle’s hand paused, then slowly moved to the back of his neck, fingers brushing lightly as if checking for something. His brows furrowed. Riddle looked around himself. In the left in the right and there was no one near him, no one touching him. What in the...
Ace leaned forward just a little. The spell worked. He'd almost thought he'd forgotten how to cast it. Though it would have been better if he had.
Riddle twitched more noticeably this time. His shoulders hunched slightly, his teacup lowering a bit too quickly as he carefully set it down before he could spill it. There's something funny going on. His one hand moved to his side, then his stomach while his another roamed across his knee in an attempt to soothe the strange buzzing under his skin. His movements controlled but uncertain. Like he didn’t understand what was happening.
Ace felt a faint grin that started to grow on his face. Hoo boy, here it goes. "Snrk—!" His breath hitched mid-inhale, shoulders jerked sharply and his free hand flew to his mouth, clamping down against it hard. Not just to stifle the sound that slipped out, but in a desperate attempt to stop whatever was about to follow. The sensation spread too fast. Spread to his sides, his ribs, his stomach. Ace squeezed his eyes shut, his grip on the pen faltering as his body curled in slightly.
Right. Right, of course. He knew this would happen. He knew this that the charm wasn’t one-sided. Whatever the target felt, the caster felt it too. And if the target resisted, if they tried to hold their breath, to suppress the laughter, to fight it both physically and mentally then the sensation would rebound, twice as strong. This charm demanded balance.
Ace’s eyes snapped open, immediately locking onto Riddle again. Housewarden was not giving in. Even now, slightly hunched, one hand covering his mouth other reaching towards Trey's shoulder, his expression was strained but still controlled. His shoulders trembled, but he was holding it back, fighting it against it.
"D-don’t—dohon’t do that—" Ace whispered hoarsely as if Riddle could hear him from this distance. And an another, stronger wave hit him. "A-ah—!" Ace doubled over, barely managing to keep quiet as his grip on the pen shook violently. His other arm wrapped around his middle, like that would help. "Whyhy—why is it already this bad—?!" he hissed through gritted teeth, voice breaking slightly as he struggled to keep control.
Another twitch ran through him. Then another. Each one sharper than the last.
Ace's back arched, elbows digging in his sides in an attempt to push phantom fingers off his body. His eyes squeezed shut. His shoulders shaking now as he failed to steady his breathing. At this rate he wasn't sure if he will manage to hold the spell for another minute. He couldn't. He can't.
His thoughts cut off as another wave hit, and this time a short, strangled laugh slipped past his lips before he could stop it. Damn Riddle Rosehearts and that infuriating composure of his. Clinging to it no matter the situation.
But Riddle was struggling. Even from this distance, Ace could hear soft laughter slipping past his control. His hand had latched onto Trey’s shoulder, gripping tightly and shaking, fingers trembling. With his other hand, he gestured frantically to his sides, his ribs, his neck, trying to explain what was happening, even though he clearly didn’t understand it himself. Then suddenly, a sharp yelp cut through the garden, followed by a high, startled squeal. The sensation must have shifted. Riddle's shoulders jerked up as if something had struck near his ears, and he sank further into his chair, nearly tipping it as his composure finally began to crack.
And as the laughter broke free, no longer held back, no longer restrained Ace felt the pressure ease. He finally managed to breathe. The sensation didn’t disappear, but it dulled, fading into something weaker, no longer digging into all his worst spots at once. It still lingered, light, persistent but no longer overwhelming.
From a distance, the gathered Heartslabyul students were barely holding it together. At first, it had been quiet, subtle glances, suppressed smiles between one another. But the moment that high-pitched squeal rang out across the garden, the group silently cheered. A few of them clapped their hands over their mouths. Others ducked their heads, shoulders shaking. Someone actually let out a quiet, disbelieving laugh before quickly stifling it. And low murmurs spread.
"Did you hear that?"
"No way—"
"That was him, right? That was Rosehearts?"
A couple of them exchanged quick, conspiratorial glances before giving each other restrained, almost disbelieving high fives. Because really…This was Riddle Rosehearts. Riddle, who enforced rules down to the smallest detail. Riddle, who rarely so much as smiled. Riddle, who absolutely did not laugh. And he had just yelped loudly. The kind of sound no one in Heartslabyul would have ever expected to hear from their housewarden. That alone made this moment feel unreal.
And meanwhile near the bushes, someone squinted slightly, their attention shifting. "…Hey, what’s going on with Trappola over there?" Another student leaned closer. "What about him?" And every student's focus shifted from the victim to the attacker. And once they did they couldn’t unsee it.
Ace was still half-hidden in the bushes, but not nearly as still as he should have been. His shoulders shook with suppressed laughter. He kept wiping at his face removing the sweat off his forehead. His body would jump and jerk ever so slightly. Then again. And again. Small, sharp movements, like he was trying to hold something in and failing.
"…Is he?"
"Why’s he moving like that?"
"He looks…wait, is he laughing?" Confusion replaced amusement, spreading quietly through the group as more of them focused on him instead of Riddle. Because something about this didn't add up.
And back at the table, things weren’t improving. If anything, they were getting worse.
Trey Clover had moved immediately, circling in front of Riddle with visible concern. "Riddle, what’s going on?" he asked, one hand hovering uncertainly near his shoulder, like he wasn’t sure whether touching him would help or make it worse. "I dohon’t knohohow—!" Riddle’s voice broke between strained breaths and involuntary laughter. "S-something is- ngh… t-tickling me everywhehere—!" His composure was hanging by a thread.
Every attempt to steady himself only made his body jerk again, another breath hitching, another sound slipping out despite his efforts. Even Cater Diamond had gone unusually quiet, watching with wide eyes as the situation spiraled into something no one quite understood.
And behind the bushes, Ace definitely wasn’t helping. The moment Riddle tried to force himself under control again, the backlash hit hard.
Ace sucked in a sharp breath, his body jerking forward as the sensation shifted lower. "Oh no, no, no—" His hands shot down instinctively, clamping at his sides before sliding to his hips as the feeling spiked. This was WAY worse than before. "Ahah!" A completely uncontrolled laugh slipped past his lips.
"BWAHA—!! AhaHAahah! N-no!" Another wave hit, stronger, and this time it struck digging right at his hips. Ace couldn't help himself, the sound that tore out of him was much louder, much higher, absolutely unmistakable.
Silence fell over the watching group. Every head snapped toward the bushes. "…That was Trappola."
"What was that sound?"
"Ace is being tickled as well?"
Ace barely had time to register it. His grip on the pen faltered as another burst of laughter forced its way out, his entire body folding in on itself. "s-stop—! Ah, no!" The pen slipped from his fingers and the glow vanished. And just like that the spell broke.
Back at the table, Riddle’s laughter cut off sharply. He sucked in a deep, shaky breath, then another as the sensation vanished completely. Then he sank back into his chair, completely limp, one hand still loosely gripping the edge of the table.
And across the garden every single eye turned toward Ace.
–––
"Off with your head!" Riddle Rosehearts shouted, flicking his wand toward Ace Trappola, who stood before him with his arms crossed.
Ace, he didn’t look particularly guilty. More sulky, even annoyed. His lower lip jutted out slightly in a faint pout, and his eyes darted irritably between the surrounding students and the housewarden. After all, it had been their idea. Their request. They should’ve been the ones ashamed. And yet they did looked guilty, to his surprise. They looked Nervous. Like they were afraid Ace would expose them and get their heads taken off too.
But their heads weren’t going to roll across the floor. Ace was the only one at fault here, and Riddle wasn’t aware of their involvement and wouldn't, cause Ace had no intention of giving them away. He accepted his punishment quietly, letting out only a small sigh as the collar locked around his neck. He said nothing.
"I can’t believe it," Riddle said, sharply turning away from him. His cape swept through the air before settling softly behind him. "Who would have thought such a spell even exists… and that someone as irresponsible as you knows how to cast it." He shook his head. The whole situation refused to settle properly in Riddle's mind. There was something almost ironic about it, enough that he might have scoffed at the thought.
The sharp click of his heels echoed as the housewarden began to walk away. The crowd shifted around them too, parting awkwardly before the housewarden spoke again. "Though I am glad you received your share as well," he added.
Ace looked up at him, raising one eyebrow. “What do you mean?” he asked, lowering his arms. One hand came up to push the heavy collar slightly upward so it wouldn’t press so much against his shoulders.
"that the spell works both ways," Riddle replied. "It is… reassuring to know I was not the only one humiliated."
A/N: okayokay Ig I need to explain the spell a bit cuz why not. So a normal "tickle charm" where one person casts it and just stands there unaffected?? yeah no. that’s lame. and unfair. we don’t do that here
So this one works 50/50. Like both the caster and the target feel the effects at the same time. same intensity, same sensation. if the target just lets it happen and doesn’t resist at all, then it’s completely equal on both sides.
BUT.
The moment one side tries to fight it, aka holding in laughter, tensing up, trying to stay composed then the spell basically goes "oh? u wanna resist?" and redirects the extra intensity to the other person. So basically:
target resists → caster gets it worse
caster resists → target gets it worse
It’s literally a fairness-based spell. like built-in karma. which means the only way to survive it is to just… give in. And yes. ace knew exactly how it works. That’s the thing