The Weird Invader: I'm Going Crazy Killing in the Human World

[No System + No Formula + Decisive Killing + Male Lead Crazy + No Female Lead + Cthulhu + Dual Worlds] Before the sun rises, the night still lingers, the lantern bearer walks slowly. In a world shrouded in mist, dirty and dark corners, shadows in the distance whisper, gruesome chewing sounds, bloodstains on the walls, vines entwined around the building, looking at the sky, tentacles are wildly waving! But the lantern bearer hides in the mist!