Ano Hito no I ni wa Boku ga Tarinai

Ano Hito no I ni wa Boku ga Tarinai manga summary: Funatsugi Makie is in love with a girl who just so happens to have a voracious appetite. Little does he know, despite acting as normal as any middle-high-school-aged girl, she's actually an eldritch horror in disguise. Psychological horror and romantic comedy shenanigans ensue.