Tired of being hated, a clever rat creates a fake bushy tale to blend with the beloved squirrel's, but must keep up the facade or lose the squirrel of his dreams.

Nice logline, seems like it would be a good pixar/disney type movie! Would definitely be interested to hear more of this.

Great Idea, got my attention, lot of promise in the premise. some questions to consider as it sounds like your still in outline stage.

Just remember if you go the romeo & juliet lovers route, that its you'll need to distinguish it from Pepe Le Pew. 'my darling'

inter-species love is always a tricky one to pull off to feel plausible (all the way to the end), so besides the tail, what is it about the two characters that draws them together. (when that love is broken what does the hero overcome to bring it all back together just as a himself a rat?)

Is it romantic love or plutonic (think bee movie). when does it get creepy.

who hates him, his own kind or humans? (why is that important?)

what is the hero journey, is it avatar like where he must choose to be or the other, what obstacles does he have to overcome to be accepted by squirrels.

Is there a bigger problem that affect both rats and squirrels that he must unite them in to over come... say something in central park??

good luck.

Love where this is going. Great longline!