NOTE: I removed the tiny little bit at the end to lengthen it and make it its own chapter. Sorry for the confusion.
Draco POV
For the first time since they'd arrived at Grimmauld Place, Harry didn't show up for dinner. Draco sat alone at the table, staring forlornly at Harry's untouched plate, long after he'd emptied his own.
Kreacher had fetched him from the library, just as he'd let the last book fall from his fingers. His head was swimming with knowledge, ideas, thoughts set down by Masters Black over the centuries. He was grateful for his ability to memorize passages of text – more grateful than he'd ever been. Somewhere in those blocks of text was the solution to creating protective wards for Harry – he just needed to reflect on it for a bit and he'd have it. He felt a bit of his fear and tension ease, draining off of his shoulders like melted butter, as he accepted the strange certainty that seemed to come both from somewhere deep within himself and from outside. The House, he realized. Of course. That the House had provided the answer, when he hadn't been entirely sure of his question, reassured him. His connection to the House was growing – he'd sensed as much, the past few days, but it was good to be certain – and he hoped that Harry's connection to the House was growing too. That must be how he knew there was a floo call. Draco's trust in the House was growing too, though he knew Harry was still reluctant. But then, he's never lived in a Pureblood House before. He doesn't know what it's like to be so intimately connected, so very much a part of your home. Draco had felt it before, of course. At the Manor. Before Voldemort moved in.
Draco cut off that line of thought with a shudder. It didn't matter. He'd never go back to the Manor. But he didn't mind so much, now. He ran a teasing finger down the wall, a stroke of affection. Yes, he could live here. He could be at home here. Especially if Harry were here with me… But Draco wouldn't let himself dwell on the future. It would distract him from the present. And if I want a future with him, I have to protect him. He's my responsibility, now. The wall hummed an agreement against his fingers, and Draco smiled. "You like that, do you?" he asked quietly. "Well, since you agree, may as well make it binding." He cleared his throat, stroked the wall again. "I vow to protect Harry, on my life and honor, on my magic and blood, the Black blood that binds me to you. I will make sure he survives what is coming, and return him to you, no matter the cost to myself. I swear it." The wall thrummed again, a sound rich and sweet as honey. And since protecting Harry is more important than anything else… I need to find out how to contact Hermione. I'll need her help to recreate the wards for Harry.
The curling warmth that had been growing in Draco's stomach since he'd made his impulsive vow to the House curdled and grew cold. Harry had disappeared all afternoon. At the time, Draco had been grateful – he couldn't learn what he needed with Harry there. His very presence was distracting. I suppose I might have been a little warmer. He's not used to Slytherin manners. Nor to Malfoy ones, I suppose. I didn't mean to drive him off forever! Draco searched his memory, wincing at the coldness he'd used to brush off Harry's offer of help. Merlin. I called him 'Potter.' What was I thinking? He'd not been thinking – nearly all of his attention had been occupied by the books he was wading through. And I'm not used to his Gryffindor manners, either, he admitted to himself.
Groaning at his stupidity, Draco surveyed the cold, congealing food with distaste. He vanished it with a careless wave of his wand, and then stalked past Kreacher, ignoring his squawked protests. He marched up the stairs, expecting to find Harry sulking in their room. But, no, it was empty, and showed no signs of Harry's having been there. With a sudden burst of fear, he checked the room Harry had stayed in, that first night, but it was empty too. Harry's trunk was still there; nothing seemed to be missing. Draco relaxed slightly. He sat on their bed for a while, waiting. When Harry failed to show, Draco mechanically brushed his teeth and readied himself for bed. He stalled as long as he could, drawing out the rituals that usually soothed him. But he drew no comfort from them, and eventually he could think of nothing else to do. He crawled into a bed that suddenly seemed much too large, and pulled chilly sheets up to his chin.
Huddled alone in bed, he missed Harry acutely. The room seemed empty without him, cold. Harry was his sun. He always had been, but it was different, when Draco was admiring him from afar. Now that he'd felt his warmth up close, Draco knew he'd always be cold, without him. Merlin. Do I – does that mean I love him? He frantically searched through his memories of the past weeks, analyzing their actions, his responses to Harry. I do. I fucking love Harry Potter. When did that happen? But that was easy – he'd always loved Harry. Even when he'd been 'Potter,' a name spat in supposed hatred, Draco had loved him. The realization chilled Draco even further. He was a liability for Harry, now. He'd make Harry's life harder. I can't tell him. I can't tell anyone. If I want to protect him, he can never know. Draco closed his eyes, trying to shut out the realization. In order to save Harry, Draco would have to break both their hearts.