When the trio were hiding in a rather rich town, they sent Arthur to scope out a rich house, going undercover as a bodyguard for the family's eldest child. At first he assumed he would hate them, assuming they'd be a rich snob--but in fact they were nothing of the sort, a kind sort of person blessed with money Arthur could only dream of. Now he just lingers around, following them around and becoming friendly, trying to either get rid of his crush or make sure they feel the same.