Wo is Mo Monster's evil nemesis. Wo first appared in The Mo Movie: Freak Out.

Wo is recycled from the season 2 Mo.

He's also the first villain in The Mo Movie: Mo vs. Wo.

He hates Mo because he's jealous that he has his own family sitcom, which he has always wanted. Wo has tried stealing shows before, which makes him a wanted criminal.

In Season 4 Episode 3 Wo made his last appearance of 2014, as seen when he got defeated by The Teenage Mo-tant Ninja Monsters (A parody of Teenage Mutant Ninja Turtles). Wo almost looks just like Mo Monster, exept for the eybrows and the black jacket. After a 1 year absence, Wo returns to S5 EP3, a Star Wars episode along with Timmy Goodman with new eyes and eyelids hearing aids and a cane.
The Mo Show - Wo