A teenager gets kidnapped by cosmic horrors one random night, then rescued by a cheerful silver-haired girl who reveals she's an ancient Lovecraftian deity wearing human skin like a costume. The show burns through absurdist comedy at light speed, treating existential dread as setup for punchlines. Nyarlko herself is the joke and the heart, a shapeshifting god with the personality of an obsessive fangirl, treating the apocalypse like a dating sim where Mahiro is the only valid route. It's gag anime that somehow makes you care about a romance between a human and something that shouldn't have emotions at all.

Mahiro Yasaka is an ordinary high school student until the night aliens come after him. His rescuer is Nyarlko, a Cthulhu deity with no fixed form who can become anyone she likes, though she usually looks like an unremarkable girl with silver hair. The result is a short-format comedy with a science fiction twist, built around a regular teenager and the cosmic being who saves him.