Ms. Moka has taken over a class of naughty kids in place of a teacher who is on maternity leave. The three naughty boys are excited by Moka Momoka's plump breasts, and from the first day of school, instead of greeting them, they do whatever they want to her, touching her breasts and peeking at her panties. During art class, they insist that it's art, and make her wear a risqué swimsuit so they can touch her all over, and before gym class they take a peek at her changing, showing that they are at an age where they are very curious about sex. Then, during health and physical education class, they ask, "I want to know how a baby is made!" and end up getting a practical lecture using the teacher's body...