Party Pat

Party Pat appears in "Belly of the Beast." He seems to be the leader of the Bears partying in the Giant's stomach, Finn and Jake found him lounging on the Giant's heart, which is described by Cubby to be like a "blood waterbed." Finn and Jake try to reason with him to get the bears to leave the Giant, but, failing to realize the severity of the situation, they only party harder to the news that they're in a giants stomach.

Appearance
He is taller than the other bears of his tribe and is the only one who wears clothing and shoes. Pat is much more human-like than the other bears. It's unknown if he is just a special mutated bear, or a member of a different species entirely. This is, however, probably just due to his character being based off of Pat McHale, the series' creative director.

Personality
For the leader of the party bears, Party Pat is surprisingly calm and stoic. He generally sports a blank, unresponsive expression, as if he is deep in thought. He speaks in a calm, decisive manner, giving him something of an air of wisdom, however this may just be a front. Despite his sophisticated manner of speaking, he is not above jovial pranking. He treats partying as spiritual practice, and a way of life, rather than just something one does for fun, and takes partying very seriously, holding it above all other things, including the safety of himself and his people.

Trivia

 * Party Pat's appearance is based on Adventure Time creative director Pat McHale. This is the second character created based in Pat, the first is the Gingerbread Pat, one of the gingerbread men based in staff members.
 * He essentially looks like a Hipster.
 * In the adventure time panel at Wondercon in San Francisco, Pendalton Ward said that Party Pat was the son of Party God.