Adult Only Institute 2: Hyeonchang and Yoonji have sex for the first time to celebrate the 1st anniversary of their relationship. Because both of them are clumsy, sex only hurts. They remain scars to each other. Hyeonchang is suffering. With the introduction of a local senior, he enrolls in Cheongbul academy, which teaches the skills of sex. Hyeonchang learns several skills and graduates. Meet Yunji again and enjoy the sex he learned at Cheongbul Academy.