Mako, his mother's friend, is on a business trip. Meeting her for the first time in a long time, Atsushi, her son, remembers the excitement of his first love. When they meet again, Mako is even more beautiful than he remembers, and Atsushi, unable to contain his excitement, sneaks off to the bathroom where she is... Mako notices this, and, frustrated with her own sexual frustration, she kisses Atsushi on a whim. However, once her body is aroused, it can't end with just a kiss, and her lustful desire continues to grow, destroying her reason and her desire to seek the young man's cock...