Kerthe (or Certhe) was one of the daughters of Thespius, King of Thespiae, Boeotia. She was one of the forty-nine of his fifty daughters to sleep with Herakles while he was in Thespiae. She would bare him Iobes.
King Thespius & Queen Megamede
Spouse & Lovers
Herakles (lover for a night)
"by Kerthe he [Herakles] had Iobes - Apollod. Biblioteca 2.7.8