Immortal Kiss

During a routine eradication mission, vampire hunter Raven drives her blade through the heart of an unknown vampire, only to discover the ancient bite mark on his neck perfectly matches the scar above her collarbone. A mysterious man named Damon emerges from the shadows, claiming that six hundred years ago, he pulled her back from the brink of death with his own blood and granted her immortality. As his blood servant, her memories were erased by Victor, leader of the hunter order, who remade her into a weapon tasked with hunting her own kind. As the resonance of their blood covenant awakens her buried memories of the 17th century, Raven gradually uncovers the truth: Victor’s bloodline has exploited the toxic blood bond between her and Damon for generations, plotting to annihilate the entire ancient vampire clan. When all lies crumble and her true identity awakens, Raven faces an agonizing choice — remain a manipulated killing machine, or ally with Damon to burn away six centuries of hatred. In the end, the blood covenant is broken. Damon reverts to mortal form, while Raven retains her immortality. They spend sixty years together in a rose garden, long enough to grow old, and long enough to love each other for a lifetime.

Synopsis from DramaGo.