The flapping of a butterfly's wings splits Romina's universe into two alternating, parallel timelines. In one, Romina is abandoned by her biological mother and raised by another family, becoming involved with her brother German in a relationship where their mutual desire is forbidden. In the other timeline, Romina is not abandoned by her biological mother, and fate brings her and German together by chance, opening up the possibility of a permissible relationship that, for some reason, fails to develop.