NACR-163 Art college student with a perky ass, Mihina Nagai

I'm Mihina, an art student. I had to draw a male genitalia for a school assignment, so I asked my boyfriend to be my model, but he started making advances on me midway, and I couldn't get the assignment done... I was worried, but he said, "If that's the case, I'll help you!" So I asked him to help me... But when he was completely naked, his penis was rock hard...