Regarding the impossibility of defeating Lily through her satisfaction, I think that's a great detail, even if the author didn't intend it that way.
After all, it's a logical ending for such a hero—to become a toy For Futa that will never be fully satisfied. Especially since rabbits are famous for their love of reproduction.)
On the other hand, it would be interesting if the game had a way to deprive Lily of her infinite lust, perhaps by removing some curse that makes her unsatisfiable. But I'm just sharing my fantasies.
In any case, the game has just entered the beta stage, so let's forgive the author for the unfinished balance.