Who knew falling in love with your best friend's little sister could hurt so much?

Hartley always heard people refer to their lovers sweeping them off their feet, but they never expected it to happen quite like this. Mostly because they didn't picture happening after being punched in the face. They definitely didn't picture the girl who punched them to insist on driving them home... or to turn out to be their roommate's sister.

Hartley barely cares about rules in their life, but the one rule they rigidly stick to is not dating with their friend's siblings. Even Daria, the beautiful little sister of their roommate. But when they get snowed in together, the tension between Hartley and Daria is increasing, and Hartley is finding it harder and harder to pull away.

Perhaps some rules are made to be broken...