They knew from the moment they saw each other that it was love.
It was in year 6 when Hermione finally decided to tell him. She was walking down the hall to meet him when she saw him arguing with Pansy.
"Pansy, that's complete rubbish and you know it. Why would that Weasley boy ever be interested in you? He's in love with Granger."
"I'm telling you! Crabbe said he overheard him telling Potter that he wanted to-"
Pansy turned and noticed Hermione watching.
"Draco." She tapped him on the shoulder. "Look."
Draco turned and waved to Hermione. "Hello Granger." He turned to Pansy. "I better getting going. I was supposed to meet Granger in the Room of Requirement ten minutes ago."
Hermione grabbed Draco's arm and pulled him to the door. The room had a couch, a table, and two chairs.
"Granger, why is there a couch?"
"Well I don't know, Draco. I only asked for a room necessary for the situation." She lied.
She sat down at the table and motioned for him to sit next to her.
"I have something very important to tell you. You must listen very clearly. Draco Malfoy, I am in love."
"What exactly does this have to do-"
"With you."
Draco's mouth slowly curled into a grin. "You don't know how long I've been waiting to hear that."
He grabbed Hermione's face and pulled her in for a kiss. She was surprised at first, but then started kissing back.
She pulled him out of his seat and over to the couch. Clothes started flying and Draco muttered a locking spell at the door. Twenty minutes later, they were worn out and conjured up a blanket. They fell asleep naked in each other's arms, perfectly happy.