Meeting Blaise
Harry had never been so grateful that he had thought to tell Uncle Vernon that the train would leave an hour earlier than it really was. By the time they got there he was sure that if he had told him the real time he would have surely missed the train and ended up stranded in London.
He rolled his trunk towards where 9 3/4 was supposed to be located only to stop short and look confusedly back and forth between platform 9 and 10. Where was it?
Harry was starting to think that all of this was some sort of elaborate joke when he caught sight of a tall dark skinned woman in an outfit that at first glance could be mistaken for just a long purple dress but was actually like the robes Harry had seen in Diagon Alley.
She strode through the crowd confidently not caring about how she stood out among everyone, but Harry guessed that the robes weren't the only reason people were staring at her. While Harry didn’t know or care much about girls he had seen the type of women that were in Aunt Petunia's magazines and in Dudley's action movies, and she looked like she could be in either of them.
This wasn’t what caught Harry's attention though, it was the dark skinned boy who was also in robes trying his best to keep up with the woman's long strides pulling along his own trunk that had an empty owl cage attached to the top of it.
The two of them were heading towards him so he took a deep breath and when the woman came close he opened his mouth to ask her help only to swallow his words down quickly when she didn’t even bother to glance at him and walked right past him and through the wall between platform 9 and 10.
He stared at the normal looking brick wall, which was decidedly not normal, in befuddlement for a moment before he turned to the boy who seemed to have stopped in place and looked nervously at the wall too. He seemed then to notice that he was being looked at and turned to Harry with an eyebrow raised, all signs of nervousness gone to be replaced with an easy confidence.
Harry looked around them for a moment to make sure no one could hear him before leaning down to speak to him. “Are you a wizard too?”
The boy's eyebrow seemed to have risen even higher. He looked Harry up and down examining him but he didn’t seem bothered by the hand-me-downs Harry was wearing or to care too much about Harry's appearance. If anything he looked amused which took Harry back for a second not used to seeing amusement directed at him that wasn’t at his expense or in hostility.
“I take it you are new to all of this aren’t you?” He asked lightly, to which Harry nodded nervously. “We just have to walk through that wall, you won't even feel a thing.” He answered confidently but something about his voice made it sound like he was just repeating what he’d heard.
“Want to go through it together?” He asked Harry as if he was being very gracious. Harry looked over to him wondering if it was a trick but he didn’t seem hostile so nodded in agreement.
The two of them pushed their way through the barrier at a light jog pushing their trunks in front of them. Harry couldn’t help but close his eyes as he felt they were about to crash but when nothing happened he opened his eyes and breathed in a gasp at what he saw.
~~~
I imagine that going from here Harry would go to sit with Blaise on the train and meet the other Slytherins (or future Slytherins). He would be confronted with the bias that had already been taught to him. Blaise would say that he thought he would be sorted into Slytherin himself. Knowing his friend, Blaise, would be a Slytherin and with the Hats the recommendation, Harry finds himself sorted into the House of Serpents.
This changes everything and nothing at all.