Jeffy Jeffy-Marvin, commonly known as Jeffy, is a prominent and controversial character in the SML series. He is the adoptive son of Marvin and Rose, and was originally the child of Nancy and artist Jacques Pierre François. Jeffy is known for his unusual appearance, characterized by a blue helmet and a pencil lodged in his nose. His behavior is often mischievous and unpredictable, creating chaos and frustration, particularly for his adoptive father Marvin. A fanart cursor featuring SML Jeffy and his iconic pencil is a perfect nod to his quirky persona.