Bill was at Scribbulus. Apparently they needed a fancy quill so that everyone could sign the guest book. Needing to get away from Mum and Fleur and all of the endless discussions about the ceremony and reception, he'd volunteered to get it.
As he'd walked the short distance from the Apparition point to the quill shop, he kept his hands in his robe pockets, fingers curled around his wand and his head down.
The quill shop had only one other customer. One with flaming red hair. The tosser hadn't even bothered to respond to the invitation.
"Percy," he said brusquely, moving past his brother to look at the nicer quills.