These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Between Konoha and Kazushi. The following exchange happens in the third OVA:
Chia: Konoha-senpai! Here's what I heard! You and Akutagawa-senpai had your first sexual experience on your first date too! Konoha: Takeda-san!
And before that, Nanase's friends tell her about a rumour going around that the both of them are gay.
Les Yay: Maki sure has some interesting ideas of what Tohko can do to repay her favors. The second book confirms that Maki has feelings towards Tohko. And Bi the Way, she wouldn't mind painting Konoha naked either.