Bad Milo

In "Bad Milo!", Ken Marino stars as Duncan, a man whose unusual stomach problems are revealed to be caused by a demon living in his intestines. After a polyp forms into a 2-foot-tall sentient being, known as Milo, the creature begins killing those who cause stress in its life, leading Duncan and his therapist to try and bond with it. As Milo wreaks havoc on those around him, Duncan must find a way to calm it down before it's too late.