Harry Potter: The skeleTON of PUN!

At the end of second year, Harry, Ron and Hermione(much to her displeasure)decide to become unregistered animagus'(you may be wondering, how could they get their hands on an animagus potion, let alone three. Well Hermione made it of course, because if she can make a polyjuice potion, which is significantly harder to make than an animagus in her 2nd year then the task should be a piece of cake). After Harry sneaks his potion into his room after school had ended and waited for the potion to thaw(which is a week I think), he drinks it only to find something he, or the wizarding world to ever suspect. (Harry Potter/Undertale Crossover)