Nell was late. He knew Harry had told him to be careful, but he trusted Léon to return Nell on time. They'd both been distracted however, and it wasn't until the ambassador's secretary had arrived to remind him of his other duties that they realised time had over-run. The driver had brought him back to the end of the street and Nell had walked the rest of the way.
He turned up his collar against the cold of the night and knocked at the door. Hopefully Harry would not be too angry with him, or Will would be on door and Nell could be sweet to him if he promised not to tell.