Please Replenish My Yang Energy!

One day, just before the spring performance, Jung Ah-young, a theater and film student, experiences an ominous incident when her protective charm snaps. Following this, she is plagued by unexplained fever, exhaustion, and nights where she loses control of herself. Behind it all is a "lust demon," a parasitic entity preying on human desire!
To alleviate her strange symptoms, Ah-young spends the night with her childhood friend, Kwon Seo-chan, and begins to rely on him. However, shortly after, Kwon Yi-chan—Ah-young's first love and Seo-chan's older brother—returns to school, causing a subtle rift in the relationship between the three. Amidst a tangle of emotions and confusion, the influence of the lust demon deepens, eventually leading to an irreversible conflict between the brothers…
Will these three be able to transcend desire and the curse to find their own answer?