Translated from original post:

This story is intended to be about a young male adventurer who infiltrates a castle where succubi are hiding and gets corrupted by the succubi.

I love the setup for this:
a wannabe adventurer finds lost pets in his village, then thinks he can take on big boy monster-slaying work,
the quest giver notices how weak he looks, but thinks "Eh, he seems confidant, maybe he knows something I don't."
he doesn't think that the monsters keeping away from the castle is a red flag,
he fucking forgets to bring (or maybe he just didn't keep it in an easily reached spot) his weapon and loses to the very first monster he encounters.

Is there a male equivalent for kusogaki, or is kusogaki genderless? Cause this is some serious kusogaki behavior.

Base +14