Percy the Polite Dragon is a dragon who was raised by Popeye's great-great-grandfather as his adopted son in the 1960 Popeye the Sailor episode "Popeye and the Polite Dragon". He is a talking dragon with a "built-in Oxford education", having a high level of intelligence.
In the episode, Percy was left at the door of Popeye's ancestor by his mother Darlene Dragon during a snow storm. Popeye's great-grandfather then raised Percy like a son even when he proved to be of great intelligence, and both happily lived together until he grew up, where it was decided that he needed to live on his own. However, after leaving home, he was captured by Brutus' ancestor, the "Dragon Exterminator". Popeye's ancestor then encouraged Percy to act like a true dragon, allowing him to use his fiery breath and scare Brutus' ancestor away.
Percy was later shown to still be alive in the present day, where he made his way to Popeye's house and scoffed at Popeye's claim to Swee'Pea that his great-great-grandfather's tale and his existence were fictitious, much to Popeye's surprise.