Hermus

In Greek mythology, Hermus (Greek: Ἕρμος) is a name attributed to multiple characters.

River god
Hermus is the god of the river Hermus (modern Gediz river) located in the Aegean region of Lydia (modern Turkey). Like most of the river-gods, he is the son of Oceanus and Tethys. He was the father of the Lydian nymphs.

Son of Aegyptus
Hermus was one of the sons of Aegyptus, by the naiad Caliadne. He married (and was murdered by) Cleopatra, daughter of Danaus and the naiad Polyxo.

Athenian nobleman
Hermus was a nobleman of Athens and a companion of Theseus. When Theseus founded the city of Pythopolis, he left Hermus there. A place in Pythopolis called the House of Hermes was named after him, incorrectly changing the name to that of a god.