Little!Senku Headcannons:
Senku would have a fluctuating headspace, meaning the regression age isn’t necessarily set in stone. While he does typically lean on the younger side, it’s not always predictable. Sometimes he is just a baby, other time he’s an enthusiastic kid who wants nothing more than to dive headfirst into something complex and scientific. I’d like to believe this is simply because Senku struggles to maintain a proper work schedule and in turns tends to overwork himself. With that, his brain seems to exhaust itself into regressing.
Xeno became aware of Senku’s coping mechanism back when he was taken by the kingdom of science. At first he treated it more as a psychological study, determined to find a more concrete explanation for Senku’s regression. Yet, the longer he was held captive the more he began to understand the importance of Senku’s headspace. The teen needs some sort of relaxation amidst the heavy weight of the world on his shoulders and who was Xeno to judge. He’s seen men resort to much worse for much less.
It isn’t until after the mission to the moon where Xeno and Stanley become Senku’s official caregivers. Stan is referred to as Papa and Xeno is Baba.
Xeno is a logical caregiver. He is observant. If the little is subconsciously gnawing at his cheek or chewing on his sleeve, Xeno is quick to pull out a pacifiers and pops the item into Senku’s mouth. If the little is beginning to whine or fuss when presented with a suggestion or question, Xeno knows it’s time to put Senku down for a nap. He seems to have the answer for everything thrown his way, and continues to uphold a safe space for Senku to regress, regardless of reason.
Big softy! Xeno loves to snuggle up with his little. Whether is pre naptime cuddles or bottle feeding snuggles when Senku is small, he lives for it. There have been a multitude of occurrences where Stanley will waltz into the lab to find a regressed Senku planted safely on Xeno’s lap. Happily babbling at his caregiver as Xeno nods in acknowledgment, cooing at the adorable display in front of him.
While Stan is also logical, he tends to lean on the more playful side of things. When it’s Stans turn to wake up Senku from his nap, it’s usually done in one of two ways. He’ll either slowly draw the little from his sleep by removing the covers and rubbing his back or chest, while speaking to him in a soft voice… or scoop Senku up from the cot, teasing the baby about his crazy bed head, or chuckling at how Senku snuggles closer to him when he first gets up, still slightly in a clingy mood until the poor baby is all flustered.
Stan likes to tease the little. Not in an aggressive or patronizing, but in a light hearted and goofy manner. Examples: popping a paci into Senku’s mouth while he’s babbling. Telling the little he is too small to do mundane tasks, even if Senku isn’t. Cooing obnoxiously at anything his little is doing. Nothing overly mean just small actions that Senku fussing and blushing. If Stan notices that he’s gone too far, either if Senku starts to close in on himself or tears begin to well at his eyes he’ll immediately drop the bit. Stan will level with the little and apologize, no excuses just straight up “I’m sorry, kiddo”
He loves picking the kid up for no reason. Senku could be on Xeno’s lap while his caregiver works and Stan will round the corner, pluck Senku off of Xeno’s lap and just walk away. He’ll take the kid outside for some time in the sun, or to Senku’s room to play with some puzzles or other mentally stimulating activities.
While Xeno and Stan both don’t participate in the babytalk, they do have a plethora of nicknames for Senku. Baby, Bud, Buddy, Button, Kiddo, Little One, Little Prince, Little Scientist, Little Mister, Muffin, Pumpkin, etc…
Senku has a huge oral fixation! If he can’t find and/or feeling too old for the pacifier he’ll be found chewing on his sleeve ruffles. Because of this Stan and Xeno have the tendency to carry around pacifiers. For Xeno, there is usually one hidden within the inner lining of his coat. But for Stan, he had a small bag made to house the item with a metal clasp imbedded in the material to attach the bag to his belt.
Senku is not allowed in the lab unattended while regressed. Xeno must be present. It has lead to some fits in the past but Senku understands the importance behind the rule despite his distain regarding it. Yet, it normally isn’t an issue considering Xeno is almost always in the lab.
Senku doesn’t cause much trouble. He’s usually very levelheaded even while regressed, so being told ‘No’ doesn’t normally cause any sort of issues… But, somedays are more overwhelming than others. If something isn’t going Senku’s way it can cause a fit, he’ll get fussy but he rarely has a meltdown or throws a tantrum. In the off chance a meltdown happens, Stan will hold him on his hip, bouncing him about as he whispers reassuring words into his ear. He encourages the regressed little to cry, while Stan rubs his back. He’s patient during meltdowns… not so much with tantrums. That’s Xeno’s domain.
If Senku is in the middle of a tantrum, on the floor kicking and screaming Xeno will sit back and let it happen while he continues to remind Senku that they can talk once he’s gotten it all out. He’ll ask Stan to fetch him a sippy cup with water to rehabilitate the kid, and once Senku’s done Xeno will invite him into his lap and help the little drink while having a small snuggle. Xeno will talk with Senku about his behaviour and they will both come up with a solution to his issue.
If y’all have more ideas for this paring let me know!!
