Silkie

Silkie is background character of Teen Titans.

He is voiced by Dee Bradley Baker who also voices Perry the Platypus, Appa, Momo, Waddles, Wulf, Numbuh 4 and Wildmutt.

Season Two
He is one of the many mutant larvae created by Killer Moth as part of his scheme to take over the city in "Date With Destiny." When he was stopped by the Teen Titans, Beast Boy bonded with one of the larvae, naming him "Silkie," and secretly kept him as a pet at Titans Tower.

Season Three
After he destroys Titans Tower in a fit of hunger during the episode "Can I Keep Him?", Beast Boy gives him to Starfire to prevent Cyborg or Raven from finding him as they search his room. She bonds with him as well, and feeds him Tameranian Zorka Berries which makes Silkie grow so large that he is eventually found by the other Titans. Robin asks for Starfire to get rid of the creature, so she abandons him on an island with the words "Please be kind to monster" carved into a rock. Killer Moth later finds him and transforms Silkie into a monstrous moth; the now-lepidopterized Silkie battles the Titans but becomes confused about where his loyalties lie, recalling the pains and kindnesses each of his guardians had brought him. Silkie then molts, shedding his giant moth form to become a larva once again, and reunites with Starfire; after the battle, he lives with the Titans as their official pet and mascot.

Trivia

 * His real name is Larva M-319.
 * Silkie has a few episodes in Cameo before his episode 'debut' "Can I Keep Him?" He appears randomly throughout the episodes after the larvae incident - "Date With Destiny" in most cases, eating the Tameranian food provided by Starfire, though no real change was evident from it.