Han Seung-ah, a vampire with a unique condition where men trigger her libido, instead of hunger. To keep herself safe, she's built a quiet life working at a company dominated by women. But her carefully constructed world is shaken when Lee Kanghyuk, a really handsome new male employee, arrives. While everyone else is swooning, Seung-ah is plotting his swift departure. But her plans go awry, and she finds herself in increasingly awkward and perilous situations, battling the urge to sink her teeth into him.