Malfoy centered himself on the bed on his back and spread his legs invitingly. 
Harry smiled at his surrender and straddled him. He looked into his eyes below him and said, "You don't have to do this...."
"I know, Harry," Draco murmured, and reaching forward to stroke Harry's rising cock.
Harry carefully prepped him and then fucked him thoroughly. They had sex three more times that night and more over the next few days. Harry learned a lot about what Draco liked. He liked a certain amount of pain, liked it when Harry praised him and reveled in the tender parts after. Harry, on the other hand, was amazed how much he enjoyed making Draco squirm, moan and beg.
In the weeks that followed, they fucked several times a day. Harry learned more about the wants and desires of his boyfriend? partner? friends-with-benefits? Draco loved to be controlled. He loved being tied up and ordered around. He still gave sass, but would bend over any surface with a mere look from Harry. And Harry? Well, he loved every second of it. He couldn't imagine a life without Draco now. 
They would laugh about what kind of crazy shenanigans they would've gotten into at Hogwarts if they had fucked instead of fought each other. Draco said that half their fights were just unresolved sexual tension. Ron and Hermione were aghast at the sudden change from awkward roommates to partners, but after some brief hesitation, wished them the best and that they would always owl before they came over.
However, after another month of nearly non-stop fucking, Draco had just finished blowing him on the couch. He was kneeling on the floor in front of him. His hands were tied behind his back, and his knees were spread open, reveling his hard cock. Harry liked making him wait, bound.
Draco frowned, suddenly, but fixed his eyes on Harry's crotch. "Harry?"
"What's up, honey?" he asked, earning an appreciative bob from Draco's prick.
"I-I..." he murmured, blushing.
Harry leaned forward and cupped his face gently, "Hey, what's wrong?"
"I love being here with you," he whispered, tears in his eyes. That was as close to a declaration of love as either of them was going to get at that point in their relationship. 
"I love you being here, too," Harry murmured, brushing the hair out of Draco's eyes.
Draco almost purred from the attention, but got his focus back. "I can't stay here forever. I need..." he broke off. Harry could guess what he was trying to say. A life? Purpose? A break from constant fucking?
"...something to do. I can't hide here forever as your fuck partner."
Harry nodded. "I understand."
"I don't want to just be your bitch forever," he drawled.
Harry straightened up, worried. "Draco, if I haven't been... considerate. You don't have to... you don't have to be that-this all the time...."
"That's not... I don't mind this... just that... this is all I am right, now. I love how you take care of me... but I don't have anything outside of... you, and you're not here during the day. I read and clean the house every day. I want..." Draco broke off and lowered his head.
"What do you want to do? Get a job? Get your NEWTs? Umm... leave me?" Harry finished, sadly.
"No, I don't want to leave you, Harry. I just want something to do. What... do you do?"
Harry looked at him, surprised. "I'm an Auror, Draco. I thought you knew that."
"You don't wear the robes," he pointed out.