She divorced her husband 10 years ago and has been raising Tatsuya with her own hands. Tatsuya also got a job, and in April, he decided to live alone. One day, Tatsuya wants to go to a hot spring on a graduation trip. I was invited to go on a hot spring trip just for the two of us. "Thank you mom, I've always liked you ..." Emiko's heart shakes at the sudden confession from her son. After this trip, I couldn't bear to live separately. Sweet air flows, and real parents and children open the forbidden door ...