When someone always has to out do and one up you no matter what the topic is. Usually you and everyone around knows this person and knows they are fabricating this and most other stories.
Jimmy: I bought a donkey yesterday, she's really cute.
Todd: Oh yeah, I slept with THREE donkeys last night and you know what, they said I was the best they ever had.
Joshua: He "Longdicked" you again, will it ever end?