Out of Depth // Phan AU

Phil drowned when he was four,
or at least he should've, or would've if it wasn't for that...thing.
The creature he was told he created in his head. That thing that couldn't possibly exist because nothing could live in the middle of the forest in a lake he was told 'wasn't real'.
Humans can't breathe underwater.
Humans don't live in made up lakes in the middle of nowhere.
Humans don't have spiked teeth or gills.
And humans especially don't have tails.