Teen Titans (2003)

S3E10 Can I Keep Him?

Starfire takes in an unusual mutant silkworm, whom she names Silkie, as her new pet. However, after she feeds him some exotic Tamaranian food, Silkie undergoes an astonishing and terrifying transformation, growing to an enormous size. Now, Starfire faces the dilemma of whether she can still care for her cherished worm in his new monstrous form.