Recently, a trendy dark gym opened on the street where the Hojo couple lives. Mavi decided to go immediately to relieve stress, but the reality of Dark Reaction was that it was an evil gym visited by wives with drugs with 100 times the sensitivity as drinks. The effect of numbing medication administered immediately on the first day is excellent. Mabi, thinking that her sex drive has increased while exercising, goes home and flirts with her husband, but he, who is exhausted from work, doesn’t even pay attention. And then, the hand of the devil rushes at Mavi, who unknowingly returns to the dark gym.