James/Percy
James used the Disillusionment Charm. He knew that it wasn't perfect and he'd have to reappear to cast spells, but in this crowd no one would pay attention to a glimmer here and there. Too many people, and too many lights for that.
He walked through the crowd. They had targets, and they wouldn't attack until they could take both women out, which meant hanging around for a while.
He saw one person that he wanted to talk to. James dropped his charm for an instant, long enough to cast a privacy spell and then cast the charm again. "Hello, Uncle Percy. No one else can see or hear me, but I suggest you use that class to cover your lips, unless you want them to think that you're crazy. First question, how's Aunt Audrey? We haven't read anything about her. Is she all right?"