After getting rid of the big balls effect, is it possible to regain it again? Also, who else's sperm do I need to collect. I already gave the statue a bottle of the Rabbit's sperm.
you can restart the boss fight against mushria to get the big ball debuff again.
and i don't think anyone but wuelie has that semen collection thing added. i tried activating the momo event again, but she didn't have her semen get collected, so i think it's only wuelie for now. more will be added in the future i'm sure.