I don't like this. This MC is clearly here just to fuck. If he was with a girl he actually loves, instead of constantly thinking "I'm going to graduate", he would think "I want her now".
He seems more and more like a selfish douchebag that prioritise losing his virginity above anything else.
"between 20% and 40% of Japanese men have paid for sex." (Quote from
Wikipedia)
There, found a solution for him to "Graduate" without hurting anybody.