You were basically just as nervous as everyone else in art class, knowing that after posing the people are going to laugh at you because of how small your privates might be, and that would be saying a whole lot. However, you had to do this, otherwise you were going to fail art class completely in front of the school.
You, and 4 other students have been chosen to be muses for an assignment where the rest of the class has to paint, or sculp the people who were wearing bathrobes such as yourself, while something unspeakable would happen. You weren't exactly sure what unspeakable thing that is, because your teacher never told you, but knowing the class it will probably effect your body. Each 5 muses would get a card explaining what the painters, and sculpters would make you as.