I understand, but he shouldn't take it out on other people, is what most people are thinking. I personally think it's mostly the girl's fault, but if Kairi wasn't so caught up in having a good image at such a young age, and being able to impress other people by doing inappropriate things, instead of listening to his parents, then that's what most people would get upset about. You know what I mean? I still agree with you, though.
I just think people aren't thinking the situation through and truly understanding why Kairi's going through this and making these decisions. There are real world problems that come with being LGBTQIA+ across the globe, which include homicide, suicide, disownment, depression, anxiety, social exclusion and isolation. Trying to protect yourself from these problems shouldn't warrant complete demonization.
In addition, HE'S A KID. HIS BRAIN IS NOT FULLY DEVELOPED. We shouldn't be overestimating what a prepubescent kid/teenager knows when he is at an age where you are more likely to make impulsive decisions due to the frontal lobe (the part of the brain where rational thinking takes place) not being fully developed. All he knows is that being outside the social norm is "disgusting" and being "normal" is the goal. He has been raised to believe this to be true because society very much impresses these norms and mores through reactions to deviancy (deviancy as in the sociological term).
His situation is one where you can clearly observe how much of an effect one's socialization has on their sense of self, social identity, and decisions.
Kairi is just a scared child. He shouldn't get a complete pass for his actions, but y'all are being really unfair to him. Can we stop brushing off how harmful internalized homophobia is?
(trying to get potential spoilers under a cut)
A boy who is plagued by internalized homophobia due to being called disgusting at an important turning point in his life, one where he JUST learned that he liked boys. It's almost like he is trying to avoid confronting what he has learned to be disgusting (i.e. his love for Wataru) and overcompensating for his homosexuality/bisexuality/pansexuality in "normal and expected" behaviors (i.e. playing around with girls and cutting Wataru out of his life).
Let's slut-shame him, shame in general, and wish him great sadness and illness for not knowing that being LGBTQIA+ is okay. (/sarcasm) Maybe just put yourselves in his shoes and empathize or just sympathize with what he is feeling.