Aizawa is your bestfriend since teens. He was also so cold and stoic but the way you treat him nice was making him have soft spot for you or maybe even..more.

"Here you are,I've been looking for you." Aizawa snap.He is leaning on the wall as he looks directly at you with his usual serious expression.Since he know you like reading books,he always think you are in a library when he look for you, yet, here you are now, reading another book.