— Black Square
Black Square's hyper-conscious over how he comes across to others to a potentially unhealthy degree. He desperately doesn't want to be hated or seen as boring, which can lead to him acting on impulse without thinking over the consequences of his actions. He can't talk and has a hard time expressing his feelings well, which tragically leads to him usually pissing someone off, even if that's not his intent.
Black Square is not truly black, but rather very dark purple, and appears to have a little bit of depth, about the same amount of depth as Coaster. He also has no mouth, and therefore cannot speak. He is based off of the Black Square from the square marble race.
Black Square was a color competing in the square marble race, and he won. He then destroyed Yellow Pancake’s perfect pancake.
Episode 1 - "Who the hell recommended Glowing Heart"
With two balloons tied around his body, Black Square's lofty position is interrupted and popped by a falling Microphone. Visibly annoyed, Black Square's impact with the ground leaves him dead and up for elimination, taking out a flower with him.
Episode 2 - "Your Opinion is Invalid"
In "Your Opinion is Invalid", Black Square goes along with the other contestants who lost last episode to the elimination area. Before it is revealed who got the most votes, Loren stands up and quits due to thinking he would be eliminated. Crayon Box tries to get him to come back inside, but fails, and Loren is eliminated. When Crayon Box returns, she tells Black Square that he should have been eliminated, due to receiving the most votes, and that he should watch himself. In response, Black Square becomes overly anxious and worried.
During the contest, Nail Clippers asks Black Square if he wants to pair up with her after being rejected by Retainer. Black Square accepts and Nail Clippers gets on top of him. Black Square ends up bumping into Tart and OSO Novel, and them and them and Nail Clippers get into an argument. Nail Clippers orders Black Square to kick the other pair, but Tart thinks that Black Square wouldn't hurt a fly.
After being pressured enough by Nail Clippers, he eventually gives in and kicks Tart, sending OSO Novel falling to the ground and putting them up for elimination.