Listen... Everybody who still uncomfortable with the idea Chika is in 16yo body and see it as a pedo stuff cuz his mate is around 30+Yo....
First, Chika was a grown up, a 40yo dude who was gay and was a high tier doctor, to be precise, a Surgeon. He got transfered to that world as a 16yo kid.
Second, at this world 16yo already considered an adult, thats why he can make his guild tag. So yea, he wasn't inoccent at all, he's mentally old, and he's an adult for those beastmen people.
ThAts WhY i N.E.E.D FiCtIonAL MeN to HeAl My BrOkEn SoUl!!!