A/N: I may introduce Scales in the next chapter. Enjoy!
When Harry woke from the vision, he looked to his clock. He was out for close to ten hours. That meant…
"BOY!" Harry didn't wince like he used to. He always winced whenever Vernon yelled like that. But, it wasn't nearly as loud as the beast from his dream. Frowning, he realized he would have to do research on what the beast was. Shrugging, Harry dispelled the charms and walked downstairs. When he went downstairs, he saw the face of Vernon Dursley, purple with rage. Harry was unaffected, an eyebrow raised.
"Yes, Uncle?" he asked, his voice sounding like he could be doing something better with his time. Which was true, as he could be researching his Animagus form.
"Don't you take that tone with me, boy!" his uncle bellowed, his thick, stubby finger in Harry's face. Harry said nothing. He blocked out the annoying shouts of Vernon. He understood what was happening. Marge was coming, he was to serve them, be at their beck and call. When he was asked if he understood, he nodded with a "Yes, Uncle Vernon" with that, he went upstairs to start working on his transformation.
It says that one should start small, focusing on the fingers first, then the hand, then arms, then chest, leaving the head for last. Problem was, Harry's form had two head, six fingers, and four legs. He sighed and put his hands into the Star Trek "live long and prosper" he willed his fingers to change. They did, with a lot of concentration and looking constipated. Soon, he could change his fingers almost at will, from his regular five fingers, to the three, long, spindly fingers, tipped with monstrous claws. He moved to the palm of his hand, concentrating on changing it forward and back, from human to the monstrously large hand, with bone out of the back. He smiled when he can change them at just a though, He kept this up until he reached his head. Since the beast was massive in size, and the room was small, he'd have to leave and go to the woods to do a complete transformation.
According to Scales, to get better results, he would have to will his body to do what his form can do. He looked in the mirror and willed his eyes to shift from solid emerald to fiery orange. He willed his hair to turn to smoke, like the mane of the horse, making it look the same, though it's like it's blowing in the wind. He smirks. If Marge pisses him of, he would scare the shit out of all of them. He went downstairs when Vernon called him down.
When he went down, he helped Marge with her things, putting them into the guest room. When he came down, Vernon pulled him aside and told him about what would happen if he used magic. He told him that, if Marge makes him mad, he'd do it. This made Vernon angry, but Harry was already gone, serving Petunia, Marge and Dudley. It worked so well, no incidents from Marge until around dinner, when she started insulting his parents.
(You know what she says. If not, read Prisoner of Azkaban, first couple chapters) "It isn't the father that's the problem, no. It's the mother. If something's wrong with bitch, something's wrong with the pup" Marge said, pointing a finger at Harry. Harry snapped, shifting his eyes and hair.
"Shut up, just shut up!" Vernon Petunia and Dudley all shrank back in fear at Harry's shift in appearance. Marge, however, either didn't notice or didn't care. She was very drunk, after all.
"Now, listen here, you little-" she froze as Harry started twitching and jerking. He tilted his head back, and shrieked. It was the shriek of his beast. Everyone covered their ears as everything that was glass cracked, except for Harry's glasses. The kitchen was drowned in darkness, only Harry's glowing crimson eyes shining in the dark. He turned and ran up the stairs. He grabs his clothes and trunk, packing everything up. As he left, he raised his wand in the air, prepared to hex anyone who attacks. There was a crack as large, purple triple decker bus screeched to a halt.
(You know what happens from here to when he gets to the Leaky Cauldron)