"Gyo-ha and Jun-oh were once each other’s first love, but they eventually broke up due to sexual incompatibility. Ten years later, Gyo-ha, now an investment professional searching for fresh opportunities, stumbles upon a dating app called “AM2”—and unexpectedly reconnects with Jun-oh. Wanting more than just nostalgia, Gyo-ha proposes a casual fling—an offer Jun-oh eagerly accepts. However, as Jun-oh's feelings grow stronger, he begins to fear that history might repeat itself, and that his affection will only push Gyo-ha further away. Caught between nostalgia and desire, can they truly keep things casual, or will their unresolved emotions threaten to change everything?"