Something was wrong. He had known it from the second that Bellatrix had started taunting them about where Harry was and Sirius hadn't rushed forth at once. As if that wasn't enough, he knew that something really was not right when James had started to get restless and Sirius hadn't been there, ready to join Prongs in a search of their own.
Once things around the castle eased up a little and he could go looking for Sirius, he headed off to his room.
The first thing he saw was the felt and rubber from the tennis balls Padfoot had destroyed. It wasn't a good sign, but then again Sirius had been frustrated about the whole situation therefore the small mess on the floor was not surprising. As he moved in closer, however, he saw the note Sirius had left and that anxiousness that had started to settle in earlier intensified.
'I'm going out. Be back later.'
"For Merlin's sake, Padfoot," Remus muttered under his breath as he leaned against the desk, "where did you run off to?" With a sigh, he passed a hand along his face as he tried to figure out where he could be. Diagon Alley? A pub? And how long had he been gone, exactly? Wh--
His heart seemed to make a leap as he caught sight of something under Sirius' pillow, and Remus couldn't seem to move for a moment as his mind kept repeating the same thought like a mantra. No, it can't be th-- No. No, no, no...
Once he was able to unglue himself from the desk, he walked over to the bed and lifted the pillow, and that anxiousness inside him heightened even more as soon as he saw Sirius' wand. His wand. As his thoughts started to race once more, Remus rushed out of the room and to a place where he could disapparate. There was one more place he needed to check before he could allow himself to think of the worst possibilities, and he could only pray that he would find Sirius there.
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Once Remus stepped out of Number 12, Grimmauld Place, he stood at the front step for a moment, staring blankly out ahead of him as he tried to figure out what to do next. He had come to London thinking - hoping, actually - that he would be able to find Sirius somewhere in the house. Instead, however, what he had found out had unsettled him even more because, according to Kreacher, Sirius had left the previous night but had yet to return. And if he wasn't at Hogwarts, or at Grimmauld Place, then what else was left?
Had Sirius been taken as well? What if something had happened, and no one knew? What if--
No. No, he couldn't think of that, because if he did he would not be able to think straight, and that was exactly what he needed to do. He needed to find Sirius, somehow, so he could join him and James in their search to find Bellatrix and Harry. Right now he was willing to give in to James' rashness if it meant Sirius being back.
"Bloody hell, Sirius," Remus muttered to himself once more as he set out, somehow hoping that Sirius would hear him. "Where are you?"
Looking back at the house for a brief second, he did his best to block all the bad thoughts that kept running through his head before turning back to the streets of London. Digging his hands into his pockets, he set out to...somewhere. He wasn't sure where, he had no idea where to even look, but for now that that was exactly what he would do until the time came to go back to Hogwarts and face the fact that his best friend was missing as well.
Sirius better be ready for a good lecture, he decided as he continued to walk. It was easier to focus on that and ignore the sickening twist his stomach did as his thoughts kept getting worse and worse. He bloody well deserved the lecture, for leaving and worrying him like this.