Finn likes marshall and gumball and can't pick one then he find put something that changes his life

In a very different version of Ooo, Finn is the little brother of Fionna and Pen. Everyone is in this Ooo, Prince Gumball, Flame Prince...Marshall Lee. Marshall Lee has only ever been a brother figure for Finn, but recently that's been changing. These new feelings confuse Finn because he can't help but wonder...to his dear Marshall Lee, is he Finn or is he just 'her brother'?