Hitsugi wo Aketara Koi ga Hajimaru

Tono Mayo is an editor at a major publishing company. Her work was going well, but her good-for-nothing boyfriend cheated on her and she was left alone just before turning 30... Then she found her grandmother's will and the key to the storehouse, which said, "I entrust it to my granddaughter, Mayo." She wondered why it had to be her, but when she visited the storehouse, she found a mysterious young man sleeping in a large coffin... She was awakened by Mayo's blood and found out that he was Roy, a vampire who once served the Tono family. He was immortal and was looking for a way to die...