Max (The Penguins of Madagascar)

Max the cat is an ally cat who is in poor condision. he at first tried to eat the Penguins, but when the penguins thought he was a moon cat, they gaved them Sardines, which won over a friendship with him, and again in Cat's Cradle, they helped him avoid Officer X

he ultamately joined the lougers in Spongebob and friends find atlantis. (which was by acsadent, but mostly due to Supervideomaniac's love of cats)