In truth, it had been a while since Sirius had done this in this way. He'd spent time as Padfoot in Azkaban, it helped filter out the some of the deep horrible cold of the dementors presence, it helped keep him sane. But since he'd run around embracing life as Padfoot - it had been before they'd truly gotten into the war, before they had faced the realities of the world they lived in. So maybe this was a chance to get a little bit of that back.
And Will was interesting as he talked to both Padfoot and his own dog Winston like they both fully understood what he was saying, and sure Sirius did - but he didn't know about Winston, though he didn't seem all that bothered by being talked to like that.
When the bowls were set down, Sirius moved closer a little slowly, giving it a sniff, though he couldn't help the way he lifted his head in surprise at the idea of the meal being cooked. Surely people didn't actually do that with their pets. Which made him wonder if Will had already figured out that he was more than he appeared or not.
He huffed another soft bark before he turned his focus back to the bowl giving the food a sniff, his tail wagging a little as he took a delicate bite, like he was trying to figure out if it was safe.