The Red Squib is a character introduced in part two of the episode Revealations.
Like the green Squib, Red Squib lived in Da Trees as a moving tree. He hatched moments after Pumkin and Piderman saved Baman from Tuba's Dad. Hostile to them, Red Squib attacks the group but is stopped by Squib in a attempt to protect them. The group manages to escape Red Squib, but it forces his way into Pizza Head and enters Piderman's basement. Trapped in the basement, Piderman tells him to go away by phone, but Red Squib hissed at him and hung up. It eventually manages to break through the basement's door, attacking Piderman and Baman. Baman tries to beat him with the Winter Friends Wish, but it only puts a permanent blue mark on him. Angry at the attack, Red Squib breaks the Winter Friends Wish, unintetionally freeing Wanda. He is put to sleep by Pumkin's music and throw back at Da Trees (as in the episode In Da Basement he is seen trying to pass through Pizza Head again). However in Ghost Night he is seen outside of Piderman's house, but, as it's unknown if Da Trees and Baman Piderman's world are connected by other means aside of Pizza Head, it's unknown if he walked all the way to Piderman's house or if he managed to go through Pizza Head. Red Squib, even though living with the other characters, doesn't become close to anyone. He is constantly angry and doesn't get along with them, even leaving in the middle of the Best Fwends Band concert to go to sleep (it is believed he has gone into a cocoon). Red Squib is literally a Squib look-alike, like Those Guys are a Baman and Piderman look-alike.
Red Squib emerges from this cocoon in the following episode. After when he emerges, he steals Baman's shoes and takes one of Pumkin's jackets in Ghost Night 2.
Red Squib's appearance drastically changes after emerging from his cocoon; a long arm, sharp teeth and a single glowing eye are the only features that have been visible so far.
In episode 25, We hab da problem, Red Squib gets a new, human-like form.
Red Squib's personality is likened to that of a jerk, shown mostly in the Play Da Song where it appeared aggressive and tried to attack Piderman and Baman. This lead to the theory that Red Squib is cranky and needed a nap, but it is most likely that it is just not a nice squib. It is also theorised that Squib and Red are "siblings" though this has not been confirmed. Red was confirmed to be returning in later episodes as a minor character.