“I'm actually a masochist.” One spring day in April, Hyun falls in love at first sight with Sungmin and starts a relationship with him. As they plan to happily spend their first time together, Sungmin drops a truth bomb and Hyun begins to contemplate. Safe vanilla sex, packing homemade lunchboxes, and falling asleep over the phone are the things that Hyun dreamed of, so it came to him as quite a shock. On the other hand, Sungmin may be a masochist with big dreams but is a fledgling that lacks the experience. “My lover is a sexual deviant I've only known from pornos!” vs “I'm a masochist that also feels pleasure from being submissive.” = “Wait up, baby! I'll become a S&M master for you!” What hardships must Hyun, a Lv. 1 Vanilla, endure to help fulfill Sungmin's dreams and become a Lv. 99 SM King?!