Shouma having first kisses with a buncha characters that form a huge poly ship (this isn't even all my Shouma x Hundred Line character ships involved in the poly ship, I just got tired.)
I dont think there's any game spoilers in this one.
each of these has a story, details below (there's Tsukumocest, and Kyoshika's kiss has sex involved, just a heads up!)
I wrote a lot so be prepared if you click the readmore!
Shouma x Human Leo(they/she/he/it/any): In my au, Leo is actually Shouma's datefriend (who's only called "Human Leo" in a meta perspective, not in the story). Leo is a homeless teen that Shouma took in, much to the dismay of her parents. They share their first kiss after Leo has to open up about running away from their own abusive family. Shouma, feeling guilty about confronting Leo and almost making them leave Shouma's home too, gets really upset that she made Leo "hate" her. This couldn't be farther from the truth: Leo starts licking her tears away, which turns into kisses from Leo, which turns into both of them kissing.
After Shouma's parents abandoned their home, Shouma and Leo were left to process that and discuss plans for after Shouma's graduation. They wanted to be in a poly relationship, possibly with other "dogs" (furries), and also get a license to keep some actual dogs. These plans were interrupted by Shouma being sent to LDA and forcibly separated from Leo.
Without giving away game spoilers, all I can say is that Leo and Shouma will find a way to reunite again in the future.
Shouma x Maxwell: At the LDA, Shouma is worried sick about Leo but also unsure about...everything. Due to certain spoilers, Shouma is even wondering if Leo is alive or...real at all, and her self esteem and fear keep her from fighting.
Maxwell, a fellow LDA unit, worms its way into Shouma's heart and protects and encourages her. Shouma slowly ends up opening up to Maxwell about Leo. They decide that it's okay to start a relationship and include Leo on it when they see her again.
A little after they get together, Maxwell initiates a kiss with Shouma. Shouma still can't believe she found one person, let alone two, who have feelings for her. She may not feel like she deserves this, but she'll treasure her lovers and hold onto them with her life.
Shouma x Haruki (trans girl Gaku): After joining the polycule, Haruki attempted a nervous first kiss (with tongue). It was...it was bad. Haruki's nerves and inexperience just made it bad for both of them. Haruki will get better at it.
Shouma x Moko: Moko couldn't understand Maxwell x Haruki x Shouma's throuple. Who was fighting over who? What was happening?? With an investigation, she concludes that - much to her surprise - all three of them really are in love with each other. So she reconsiders her prior bias against polygamy, and accepts the group's invitation for her to join them.
Her first kiss with Shouma was nervous on both ends but mostly on Shouma's end, because Moko is lovely but can also be intimidating, especially when she told Shouma to "Give it all you got!!" before going into the kiss. Shouma chickened out of "all she's got" and went for a small peck, which was fine because Moko was still new to kissing anyway. A sweet small first kiss.
Shouma x Darumi: Shouma figured that kissing Darumi would be exciting, and her heart was pounding like crazy before their lips even touched, when Darumi pinned her against the wall. Their lips touched, and then Darumi bit Shouma's lip as kind of a joke. It hurt but Shouma enjoyed the hell out of it! Darumi snapped at Shouma a little bit for freezing up, but she enjoyed the little squeaks she got out of Shouma when she bit her.
Shouma x Tsubasa: Tsubasa was really nervous on entering this relationship, and sometimes her insecurities would get to her. She told Shouma that if they were going to kiss, Shouma had to "kiss like you mean it!" because Tsubasa would get her feelings hurt if Shouma barely pecked her and then ran away (Shouma used to run away when Tsubasa tried to talk to her in the first days of being brought to LDA, which feels like forever ago at this point). But Tsubasa had massively underestimated Shouma's experience and confidence when it came to kissing at this point, and Tsubasa was the one who ended up freezing up while Shouma showed her that she could absolutely deliver. Tsubasa felt really bad about her judgement, but Shouma admitted that Tsubasa's prediction would have been accurate if Tsubasa was Shouma's first ever kiss.
Shouma x Kyoshika: Shouma accidentally walked in on Kyoshika...eh...with the Holy Jumonji Sword. Kyoshika and Shouma were quite embarassed (while the Holy Jumonji Sword suggested a threesome). This wasn't the first time Shouma walked in on one of her girlfriends masturba - I mean, doing something naked, but she still gets embarrassed when it happens.
Kyoshika (and the Holy Jumonji Sword) asked Shouma about joining them, and Shouma decided, why not? As they were getting closer, the two realized that they had hung out together many times, cuddled sometimes, but never actually kissed. It wasn't even intentional, they had just usually been around their other girlfriends and the two of them happened to never lock lips. Well, naked in the bed, they decided to go for it.
Shouma x Eva: Eva was brainwashed for some time, and Shouma felt guilty for having a crush on her because even with the glimpses of her true personality, it wasn't like they really knew each other, and it wasn't like Eva could really like her back...Though, in the rare moments of lucidity, Shouma was always making Eva feel better about her terrible situation, and she wanted to get to know Shouma more and more.
After her brainwashing was broken, if Eva isn't preoccupied with something else, she tries to get to know her new classmates while being her real self, and she catches feelings for Shouma pretty quickly. When Eva pulled Shouma into a kiss for the first time, Shouma knew Eva wasn't brainwashed and had her mind back, but Shouma still felt conflicted about it. She really really didn't want to take advantage of Eva. This hesitation did make some interactions strained, but Eva is determined to prove to Shouma that this is love, and Shouma's heart will be screaming until she can no longer doubt that Eva's feelings are genuine.
Shouma x Kako: Kako and Ima joined the poly group as a packaged deal (Maxwell would have felt awful breaking the pair up, even though they weren't "officially" together...despite the obvious tension between them).
Kako and Ima are also sixteen, though they pretended to be younger and they had been convincing enough. Even though everyone knew the truth now, Shouma is still getting used to that and initially feels hesitant/guilty when Kako asks for a kiss...even though, Kako is the one who asked for a kiss. Shouma stuck to a sweet peck, which was good because Kako was also new to kissing and Ima was watching protectively. Shouma's heart fluttered at how shy and cute Kako was.
Shouma x Ima: A little while later, Kako and Ima are already settled into the poly group. Shouma's hair is growing longer, and she asks about how Kako does her hair. Ima is the one who styles her hair actually (though she credits Kako for having such amazing hair that it "does the work for" Ima). Ima then ends up doing Shouma's hair the same way while they're watching TV together. Shouma is flattered by how lovely it looks, and casually thanks Ima with a kiss. Ima hadn't expected Shouma to be so forward. Shouma got embarrassed after realizing Ima wasn't expecting that kiss, whoops!
Shouma x Kurara: Kurara took her time with physical affection (and...affection in general). One morning, she ordered Shouma to come in her room and give her cuddles. Shouma excitedly agreed, though once she was being cuddled, she did get more nervous, remembering Kurara's temper. Still, she felt like she and Kurara were close enough that things would be fine, and that ended up being correct. When Kurara felt ready, she pressed her face into Shouma's, and both of them felt a little nervous, but they melted into each other.