I Athena Married the Demon of Sparta

Athena, Olympian goddess of wisdom and war, is exiled to the mortal world and reborn as Althea, the illegitimate daughter of an Athenian noble. She is forced into a proxy marriage to Charis, the notorious cruel young lord of Sparta. On their wedding day, she seizes the upper hand with her wit, only to discover that Charis is actually biding his time. The two join forces to foil the power-grabbing plot hatched by his elder brother and sister-in-law, and fend off repeated provocations from their divine foe Aphrodite. In the end, Athena abandons her immortality for love, spending her remaining mortal life with Charis until old age.