ZeniNezu Comfort
A statement from Kaigaku causes Zenitsu to doubt himself; luckily, Nezuko is here to cheer him up.
Side Note: In this AU, Kaigaku actually meets Tanjiro and the others and he does not like them the slightest. Nezuko absolutely HATES him for making fun of Zenitsu and looking down on others. She believes he's nothing but a self entitled brat who cares about nothing but himself and unworthy to succeed the Thunder Breathing Hashira.