Jake is Finn’s best friend and adoptive brother. He is a 28-year-old shape-shifting dog. His magic powers allow him to stretch or shrink any part of his body to any shape and almost any size, ranging from becoming gigantic to becoming incredibly small. Acting as a confidant and mentor to his energetic brother, Jake has a laid-back attitude in most situations, but loves adventure and will eagerly fight when he needs to. In the episode, “The Apple Thief”, it is revealed that Jake used to steal bikes and purses from old ladies. His powers help Finn considerably in combat and transportation, but are also sometimes used as nothing more than jovial forms of expression. Jake is in a relationship with Lady Rainicorn; they have five children together as seen in “Jake the Dad”. He met Lady in the pilot episode and is quite skilled at playing the viola, which houses a worm called Shelby.
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