So I know you said you will balance things once you have more content in, but I want to make a suggestion that may make that easier later on.
At present, once you have enough sex hp and do sufficient sex damage, the fuck loop can go so quickly that it is impossible to actually play the minigame and you just have to let it ride out until you lose (gaining absurd love points while doing so). To prevent it from reaching that stage, you could put a trigger on the loop speed for a win condition that gives you a large but not absurd number of love points (and maybe special text). That would be satisfying to the player while also preventing the animations from getting too silly.
Love what you have so far!