This short guide gives you all you need to make a Finn costume. Finn the human (simply Finn to most characters) is the main character of Adventure Time. Together Finn and Jake embark on crazy adventures. Finn, one of the last humans, was found in the woods at infancy and taken in by Jake’s parents. A video of the proposal shared by one of the onlookers @destructagon on TikTok has 37.5k views.