Who comes to live with the Samsas? What might be the significance of these new characters? Why did Kafka not give them names or other individual characteristics?

The family, seeing the lodgers as another source of money, is subservient to them at all times, bowing to them, not sitting in their presence, waiting until they inspect their food, and so on. Mr. Samsa, when he fears that Grete's violin playing is bothering the lodgers, is instantly willing to stop it immediately for their pleasure. In this way, the family is imprisoned in their own home. While, in the past, they could return home from the dehumanizing experience of work and relax together, now they can never relax and are always servants, whether at work or home.

The lodgers do not need names, as they actually represent circumstance.