How Could This Happen to Me

At the end of third year. Harry sends a letter to his godfather, asking for Sirius to help him follow in the Marauder's footsteps. He got his wish. And thus armed with an... unorthodox animagus form, proceeds to take fourth year by storm. Prepare for awkwaard scenes of self-discovery and cameraderie. Also, rated M for teenagers being horny and foul-mouthed eventually.