Sometime when Mariko was in her twenties, she discovered that she only had a 5% chance of having children. Mariko was just your average woman, although at the time she was with a guy who was a loser (who was later featured in Mariko's book The jigelo and I ). Mariko took the news rather harshly, and decided that she would no longer be an ordinary woman... she would become EXTRAordinary. The first step in this process was to make a hairstyle that was as strange as possible. After this change, people stared at her wherever she went, which was fine by her. It seems that at first just having hair going in every direction was strange enough, but eventually it evolved to rather elaborate head gear with a squrrel living on her head. Indeed Maro-chan has a fairly interesting life since Mariko changes her hair piece from day to day, and ocasionally more than once a day.

While Sana and her mother seem well suited for each other, there is one thing in their past which in a way haunts them. The truth is that Sana is not really Mariko's daughter. Mariko discovered Sana abandoned on a park bench, and eventually ended up adopting her. Mariko decided that in order to find Sana's mother, Sana would have to become slightly famous, and She would become an accomplished writer. Though their popularity, there is a small chance that they could find her real mother, although neither of them are quite sure what they'll do if they really find her.