Severus was so used to being up in arms about his blood purity that Alecto surprised him, and it was written all over his face. He lifted a hand to touch the side of his neck and pressed his lips together, nodding slightly.
"Of course. I sometimes forget," he said casually, though the matter always had him a bit sore, "Yes. My mother is a witch but her husband is muggle. It was the poorest decision she ever made."
When coming upon a table, he pulled out his seat and looked at it, then moved around to pull a second, leaving the first for Alecto.
He wasn't about to mention his stance on muggles and mudbloods.
"Order whatever you'd like. I've nothing better to spend the money on," he admitted, "I'll order your drinks so we aren't punted."