Xander decided to head off the disaster he could see coming, "Just so you know, my Padfoot is Sirius. You see, Wormtail is the betrayer, but Sirius isn't always Wormtail."
"What?" she asked confused.
"Aww, it would have been funny if she discovered it herself," Peter pouted.
"Not a good idea," Xander shook his head. "Sirius has a huge amount of power, but no real control yet. He's very careful when casting spells, but if he's attacked he could end up casting something reflexively without remembering. He's only been all powerful for a couple of days after all."
"Good point," Peter said wincing. "In there is a good Sirius, don't attack," he ordered Harriet.
"Okay," she promised before entering the Raunch O 'Mart and coming out as quickly as she went in, her face a bright red. "Well at least I can be sure he's not a death eater."
"Yeah?" Peter asked, trying his best not to laugh.
"Yeah, I'm pretty sure I saw everywhere the dark mark could be hidden."
Peter fell down laughing, so naturally Harriet started kicking him, making Xander laugh.