Gun, a young heir of an ancient noble family, has carried a curse since birth — an incurable blood disease that will claim his life before he turns 30. That is, until he discovers the only way out: marrying Bank, an ordinary chef who possesses a hidden power within him. Gun knows all too well that should this marriage be "consummated," Bank will die in his place. But as the days pass and they grow closer, feelings that were never supposed to exist begin to take root without either of them noticing. And as the clock ticks ever closer to his 30th birthday, the heaviest question of his life haunts him without rest — between his own life and the life of the one he loves, what will he choose?