Eventual hero or otherwise (Severus doubted the validity of what he’d been told about himself in the future for what he considered to be obvious reasons), he saw no reason to treat Sirius with any sort of cordial behavior — not even a little bit. He stepped forward once, escaping the strange electric push of the magic around them that Severus doubted had anything to do with either of them.
In that one thing, and that one thing only was Sirius innocent. But that wasn’t enough.
“I see Azkaban didn’t humble your glib attitude any,” he murmured, not even subtle about reaching for his wand. “Still so smug, even after murdering your best friends and—“ He didn’t even bother saying her name. Couldn’t, maybe. “The gall. I ought to kill you in your own bed.” Except Sirius was wandering around now, like he was more irritated by the situation than anything else.