In school, Wang Hsiao-hsia and her childhood friend Yuzu are seen as a couple, but Hsiao-hsia secretly longs for the transfer student Cheng Yih. Cheng Yih, admired for his exceptional grades, talent, and fighting skills, captivates her heart. Despite her poor academic performance, Hsiao-hsia tries various methods to win his affection, but nothing works. Unbeknownst to her, Cheng Yih harbors feelings for Hsiao-hsia as well. Meanwhile, Yuzu, fiercely protective of Hsiao-hsia, is wary of anyone trying to get close to her. As summer arrives, a fragrant first love begins to bloom among the three of them, reminiscent of lemongrass.

Risking his own life, a young swordsman must match his strength, courage, and fighting skills to slay the Devil Knight. This is no easy task as he must battle untold assassins and dastardly kung fu experts.