You feel behind you and finding nothing go back to watching the other boy. Your eyes go wide as his shoes tear apart and a pair of hooves replace his human feet. Then the pain in your rear returns much sharper this time and when you reach back you fine a bump on your rear just above your tailbone. As you rub it you hear the other boy fall down onto all fours with a loud clomping sound. "HEEHAWEEELP! MHEHAW!" He cries out drawing your attention. "LHEEHAWt mHEEHAW out HEE HAW of HEEHAWHEEHAWEEERE! I d-d-d-on't WHAWHEEHAWnt to HEE HAW HEEHAW HEEEEE HAAAAW!"
Then you feel the bump on your rear get larger followed by a loud tearing sound as the back of your pants tear open and by the time you look behind you a 6 in long donkey tail meets your eyes.
Looking back at the other boy and you realize what is happening and start to try and find a way out of the room.