Draco gets out of the bathroom wondering why Harry cared so much. He has his back to Harry and he slowly turns around. A little voice in his head yells" MATE". Draco is in shock. Harry Potter? His mate? This can't be possible. Harry probably deep down still hates him. His eyes are wide as he stares at Harry.
" Is something wrong? Is there something on my face?", Harry asked.
" Uh no. Sorry lets start to head to class."
Harry looks at him weirdly, but then says with a smile," Yeah, sure"
They both start to head to class and notice they have their first class together. They head into the potion. Their moods into the dumps as they get memories of Snape. Draco looks sadly done remembering all the times he came into the classroom. Seeking guidance depression, anxiety, or being gay. Snape answered all his questions. You see Snape found out later in life that he was gay and what he had for Lily was more of an obsession than love. Though he still protected Harry because Lily protected Severus from the bad of the world as much as she could until they separated.
So Snape started learning. He went to muggle gay clubs. He learned it all. He then came back to Hogwarts and started to teach. Helping struggling teens that needed help with their sexuality issues. So when he found out that Draco's dad started to miss treat Draco because he was gay he got extremely over protective. Every time he was around he would save Draco from his dad. He treated him like his own child especially when they were alone. And Draco thought of him as a father too.
Draco thought of all the times Snape helped him all through class. Not once paying any attention to the new professor.