Funny enough, I was just about to share an idea involving Leah's Womb.
Whenever it's the enemy's turn to attack, you'll be thrusted into a battle system where you'll have to guide an ovary inside of a womb.

To avoid taking damage, you'll have to guide the ovary away from the attacks.

Though now that I about it, this battle system is way to similar to Undertale and Deltarune. So maybe its best not to use this idea.
Here's a bonus "biting effect" for Leah's battle sprite for whenever she gets attacked (or bitten) by a Parasite Beast.

