Mizuki has built an unhealthy relationship with Ema-nee, the cool and perfect student council president. Ema nailed Mizuki to the wall, telling him that it was only for that moment, but Mizuki's fierceness was unrestrained... At the school, in the hallway, in the warehouse and at any time and place, ema is forced to show off her uncontrollable behavior. Ema unintentionally accepts it and pulls it out, but in the immoral excitement, she forgets herself and gets fucked! During her sage time, she comes to her senses and scolds her younger brother like a big sister, but the cloudiness that accumulates in her younger brother's pool is constantly being released, and he seeks her body and raises her limbs... Meanwhile, an important secret that was hidden casually comes to light and the relationship between Ema and Mizuki changes drastically...