Ichimatsu and Todomatsu fighting over Karamatsu cuz they have this huge crush on him.
Ichimatsu being the tsundere he is acts like the typical I-hate-you-but-I-love-you shy type of shoujo girl but he ain’t like Totty with his moves. He would show his affection by insulting/hurting Kara cuz his into that platonic bdsm. If he sees Totty doing shit like sitting close to his bae he would do the “fuck you i’m sitting between you two” move and punches Kara cuz that’s how much he loves that shithead.
Todomatsu is straight up with his flirting and seduces the blue boy like he shows his legs and shit, reads playboy mags with him, treats him to Sutabaa, and to the point he accidentally wears Kara’s clothes and flaunts them around for the others, especially Ichi, to see. And when asked, he’ll be like “Cuz they’re boyfriend material teehee~”
Karamatsu being dense as fuck can’t see his two bros vying for his attention and wanting a incestuous relationship with him. He’ll just be like “Y’all my Karamatsu bros~”