Quince is an alien prisoner who appeared in the episode ...Nor Iron Bars a Cage.
He is a rodent-like creature and he has blue skin. He has white hair and wears a black jacket with a brown shirt underneath.
Even though he got arrested, Quince is shown to be a justified man and he had a sense of dignity and showed distaste to an idea of killing someone. He stayed in prison as he believed he still had time to serve.
In the present, he encounters Kevin, once again mutated, and seeking revenge on Morgg for killing Kwarrel. He tries to dissuade Kevin, but his pleas fall on deaf ears.
He didn't do anything to escape from the prison like the other criminals did. When this was questioned by Gwen, he answered that he "still had time to serve."
Ben 10: Ultimate Alien
- ...Nor Iron Bars a Cage (first appearance)