Gravity Falls Inter-dimensional demon with a dark sense of humor.

Star vs. The Forces of Evil Manipulative Nine-fingered lizard man.

Adventure Time Sentient Nuclear Fallout.

Legend of Korra Giant Soul-consuming flatworm.

Over the Garden Wall Literally Satan.

Wander Over Yonder Dorky Schoolgirl with a Sadistic streak.

Steven Universe A Fandom that seems to completely and almost purposefully ignore the show's message of love and acceptance of others.