They Wanted the White Tiger. I Chose the Snake.

Wren is rejected by her childhood love, Lysander, who chooses an S-rank mage instead. She bonds with Riven, a despised black snake beastman and failed experiment. When a deadly black tide threatens the kingdom, Wren discovers Riven’s terrifying power—and unlocks her own hidden magic. Together, they expose a forbidden experiment, defeat the darkness, and overturn everyone’s fate. The abandoned snake becomes king, while the “useless” mage becomes the only one who can save him.