oo, i like the idea of kacchan being very confident on making izuku submit, even considers on bitching him. but uh oh, izuku already started on bitching kacchan and subconciously making him submit to him >:3.
izuku knows kacchan was always meant to be his pretty omega, he just needed to fix his alpha status mistake.
i haven't read or thought of alpha/alpha relationships so this is the route my thinking goes Dx
but im curious on what ideas /you/ have >:3c