Tam-Tam started life as an AI-equipped Roomba with a faulty personality chip, which led to a music obssesion. So it sought out Index, so she could modify him to be more than its roomba body. He allowed the conversion of an uzi and hover jets in exchange for the radio and speakers.
Tam-Tam is played by Tom, a newcomer to Penance RPG who is settling well into the mayhem.