atsushi being super new to romantic relationships (or loving relationships in general, but that's beside the point) so he assumes dazai will lead at first, and he can pick up on that, since dazai is the experienced one here. but dazai is utterly foreign to atsushi's soft, sincere touch, so when atsushi very timidly kisses him with all the nervousness but love all the same, dazai is the one who ends up all flustered and confused and tries to play it off by laughing
atsushi realizes then that dazai is also new to being loved so openly like this, so he endeavors to learn how to accept it alongside dazai
