After sneaking into a black-market auction, the thief Kalim accidentally steals one of the most highly priced goods: a beautiful demi-human with beast ears and a tail named Asena. Now, Kalim has to take responsibility and shelter Asena in his home for one month until the ship that can take him back to his homelands arrives. Asena, who despises humans for the way they've subjugated demi-humans, treats Kalim coldly at first, but then something Kalim never could've expected happens: Asena goes into heat.