Monster Kid in Underfell is Dr. Alphys’ younger cousin. His real name is Marshal. He might come off as emotionally distant and a bit cold, but deep down he is very lonely and just wants to be friends with Frisk, Chara, and Asriel. He has a bit of a serious demeanor, but this is because he tries to act ‘cool’ to impress others. Sometimes he tries a bit too hard though. He looks up to Undyne as well as admiring Papyrus.