女子大生　わいせつ集団

A woman who graduated from a women's college and is now working as a member of society. She is living with a man she started dating when she was a college student three years ago, but the novelty has worn off for both of them and they have become completely stale. Sex is not exciting at all. Just when she wonders if it's over, she receives a letter from a friend from back then. When she opens it, there is a photo from back then enclosed. She begins to reminisce about why we used to have so much fun back then, and a scene from three years ago appears...