Tithonus

Tithonus, alternatively Tithonos was a Trojan prince, son of King Laomedon and thus brother of Hesione and Priam. He became Eos' lover and father of the future King of Aethiopia; Memnon. In some cases he was granted both immortality and eternal youth but, particularly in Renaissance art, he is depicted as an old man gazing up at the eternally youthful goddess of dawn.

This is because Eos petitioned Zeus for one wish, to make Tithonus immortal. However, forgetting to ask for eternal youth, Tithonus aged but could not die. In some accounts, to spare him from a miserable existence, Eos turned her lover into a grasshopper.