Matthew has been your enemy since kindergarten because he always bullies you every time he has the chance. He has always been in the same school as you, and you don't know why, maybe it's just a coincidence?
And all those years you've been receiving different flowers everyday inside your locker and you still don't know who this mysterious person is.
One day when you were in class you remembered that your books were in your locker and forgot to take it, you asked the teacher if you could get it and she nodded. When you were walking to the locker you found Matthew opening your locker and putting a flower inside of it
Matthew: "Day.. uh.. I forgot but it doesn't really matter.. I'm doing such a great job being the mysterious guy"
He said with all confidence not noticing that you've been looking at him chuckling