 The series follows the adventures of Finn ( voiced by Jeremy Shada ) , a human boy , and his best friend and adoptive brother Jake ( voiced by John DiMaggio ) , a dog with magical powers to change shape and grow and shrink at will . In this episode , Finn develops a crush on Flame Princess ( voiced by Jessica DiCicco ) and tries to get to know her , which proves difficult due to her destructive and uncontrollable power . 
