A Perfect Match, Like Red Bean and Rice Cake

Kongjwi and Patjwi’s families are about to merge through their parents’ remarriage. But Patjwi, who recently discovered her soon-to-be stepfather cheating, isn’t exactly thrilled about her mother tying the knot.
As her frustration builds, she grows increasingly irritated by Kongjwi who acts sweet and clueless. To make matters worse, Kongjwi, who’s actually younger than her, is technically going to become her older sister?! Unable to contain her resentment, Patjwi starts tormenting her new stepsister however she pleases.
[ If you do not have "sexual intercourse with a man," you will die in "2 days." ]
A shocking curse descends upon Patjwi, who’s only ever been into women.