At the end I was starting to think that beast from the beginning was actually a pet, that the girl had finally started bonding with... description tells a different story! XD Feels like a weird route to take towards the end, making him/you so little human you start wondering if he is, I got the right impression from the start, but changed along with the transformation. But anyway: the animation itself was amazing, so smooth, and happy, and really going through the motions of positivity; getting to that mood. Nice work!
-cd-