Works wherein a servant, like a Maid or Butler, are pictured with their master, the person or persons whom they service. This is usually hinted at through the way they dress, where one party is in uniform while the other is dressed as they please, or in aristocratic manner.
If the servant is actively servicing a character who is not also dressed like a servant this is an even clearer example. Servicing could mean anything from Cleaning to helping another character get dressed.