The 'Boy' Who Lived and 'his' Metamorph Surprise

Harry just wanted a few hours to himself in the summer after 4th year and the nightmares of the 3rd task and the graveyard. He brews a batch of polyjuice potion and adds the hairs once he reaches Grimmauld Place with the Order, but the hairs he intended on adding were accidentally from different people; one, the ever changing Tonks, and the other a gorgeous model! It unlocks his dormant Metamorphmagus abilities, and now Tonks has to teach him how to control his new morphing abilities in time for his hearing...