I don't think that would be any relevant to him, he knows Usagi was already experienced when he met him. Guessed it right in the first chapter with that tutor.
But do you remember the scene where usagi, hiro and misaki san seen each others at the university .. and misaki san was confused how usagi san came to know hiro san .. and i wonder what kind of face will misaki san will show if he finds it out !! and i want to make him super jealous (sorry for the bad english)
I wonder when will misaki finds out that usagi san and hiro san had sex in the past ??