Mizumoto Sayaka

She has been married for 5 years to her husband (who lives alone) and together have a 3 year old son.

She has not had sex with her husband since they had a child, and has not masturbated for a long time because she has been busy raising their child.

She is always cheerful and caring. She is a bit unreliable, but her maternal instincts are greatly stimulated by the protagonist, and she is content with allowing him to indulge in his desires.

While she understands that it is immoral, she starts to succumb to his youthful desires.