That seems fine. It makes more sense for the one assaulted to be Gai, since he is less experienced than Jun. Could also be a nice starting point for Gai's crush hehe.

EDIT: @Suspect, I'm fine with whatever, but I was looking forward to writing out a scene where Gai's face turns completely red when he realizes who Jun is, and he awkwardly avoids eye contact as he pretends that nothing is wrong while stuttering with every word.

Or something to that effect :P.