It’s no secret that Ava is a ghoul. She writes books about her life after becoming a ghoul. And ghoul’s eat the dead.
Dead humans and dead monsters. Sometimes the humans are the real monsters, but that’s another story.
My point is, she eats the dead. She has a reason to keep a basement filled with dead stuff. Other people, not so much.
Case in point, a mortician that took his job a little to seriously and kept bringing work home with him. Am I kidding? Nope. Read it for yourself. Oh, the strange world we live in.