Malessica is a fourth grade student and one of Clarence's classmates. When Malessica, Kimby, Courtlin and Clarence (who was accidentally invited to an all-girls slumber party) play an origami love game, Clarence notices that Malessica is upset that Jeff may not like her. Clarence tells Malessica that since Jeff is his best friend, he can get them togther. Malessica is hesitant about the idea but the other girls are excited about it.
After a failed attempt to call Jeff (in which Malessica was too scared to say anything so Clarence pretended to be her), the girls and Clarence continue having fun until Malessica mentions that she feels bad about not telling Jeff the truth. When they get to Jeff's house, Clarence parts ways and the girls decide to go back and throw sticks at each other, Malessica having decided she's no longer interested in Jeff.
Malessica makes minor appearances throughout the series, usually as a background character in school.
Malessica has pale skin, light brown hair and has large, round glasses. She wears a purple turtle-neck sweater, light aquamarine pants with pink flowers, and black Mary Jane shoes.
Malessica tends to be depicted as something of a nerd. On top of wearing big glasses, she also has a vivid, yet geeky speaking style. For instance, in "Honk", when she and the other kids try to talk some sense into Clarence, she follows up on Courtlin's statement by telling Clarence that the horn "mega limits your vocabulary." She's also a girly-girl who likes dolls, ponies and playing dress-up.