Blue Exorcist/Tear Jerker

• Blue Exorcist starts out with the protagonist's adoptive father, Fujimoto, committing suicide to prevent Satan from taking him away. Later on, he and his brother find Fujimoto's familiar, a cait sith named Kuro, who has gone beserk upon hearing about his death. He refuses to accept it until the protagonist head butts him and offers friendship. Kuro breaks down into tears as he realizes his friend is truly dead.