Proper noun
Alectryon
(Greek mythology) A youth charged by Ares to stand guard outside his door while the god indulged in illicit love with Aphrodite. He fell asleep and was transformed into a rooster as punishment.
In a much later interpolated detail, Ares put the youth Alectryon by his door to warn them of Helios's arrival, as Helios would tell Hephaestus of Aphrodite's infidelity if the two were discovered, but Alectryon fell asleep. Source: Internet