Mothmonsterman (voiced by H. Jon Benjamin) is a giant humanoid moth creature genetically engineered by Dr. Weird. He escapes the lab through the hole left by Rabbot when he is attracted to the city by the light of Shake's "Shake Signal". When the light is turned off, Mothmonsterman does everything in his power to get it turned back on, which basically entails him manning a school bus, eating holes in Shake's flag, and calling the Aqua Teens' house about the light. Shake manages to convince Meatwad that Mothmonsterman is the bus and that the bus is Dracula. When Frylock takes Shake to Memphis, Tennessee to prove that Dracula is dead (by visiting a tourist trap called "Dracla's [sic] Grave"), Mothmonsterman takes over the house and finally gets to turn the light back on.
Mothmonsterman is an easygoing fellow, who rarely goes through much trouble to achieve his ends. He can asexually reproduce and apparently has around 1,000 children, as he "laid about a thousand of [his] eggs" is Carl's esophagus. He owns a house in Belize.
In The Last One, Mothmonsterman became a member of Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday...
- He appears to be attracted to bright lights, similar to a real moth.
- He is one of many creations of Dr. Weird.
- Mothmonsterman share's many similarities to the cryptid known as Mothman.