honestly think you need to work on the sex part
id suggest making a 2 phase system
1st is the normal combat phase this is to get your mc hard but also to destroy the enemys parasite after you kill off the parasite you move into defeat phase this lets you walk away the winner or if you can get yourself hard enough to dom them and turn them into your mate
if you breed them after getting rid of the futa virus you turn them into a healing source this would act like the first girl you fuck as she will be more controlable by the player but not remember anything that happened