Jane is a Korean American. She will stay at her father's friend's house for a few months while preparing a chain massage shop in South Korea. However, what she does is not work at a massage parlor, but sells sex toys on internet radio stations. Her boyfriend Tae-in doesn't like what she's doing and tries to make her stop. One day, Jane found out that her mother in the United States was sick. On her way home, Tae-in had a car accident. Jane is accustomed to testing her sex toys on Tae-in, so when he gets sick, her sales will decrease. So she found other men to test her toys...
《三月的狮子》改编自河内贺冢同名畅销漫画。电影分为两部分：第一部分和第二部分。第二部分主要告诉主人公对“未来”的愿景“：他将与他爱的人开始新的生活。
