My Brothers Bestfriend (NARRY AU)

Harry does his homework, he listens to Beethoven, and has a cat named Bella who he adores and loves.
Harry's mom married Liam's dad the summer before there grade 9 year of high school. When Liam has friends over all the time, Harry can't help but notice the little blonde Irish boy who is always visiting.
As they are all in their finale year in high school Niall needs a tutor, and Harry is chosen by his English teacher to help him pass the course.
As Niall and Harry become friends fast, what does Liam think of their relationship?
Will things go further for Niall and Harry?
My Brothers Bestfriend.