Unaired episode included in the fourth Blu-ray volume. The episode will take place during the same time in episode 16 (episode 5 in second cours) and depict what Eris and Ruijerd were up to outside the main story, as teased by the comment "Goblin Extermination."

Kazushi Sudou is a university student who is visited by his two childhood friends, the sisters Ayane and Kotone Shirakawa. When Ayane discovers that Kazushi not only forgot to buy her pudding but is also using her special lotion in the bath, she decides to take revenge and join Kazushi in his bath along with Kotone. Will the perverted Kazushi be able to remain indifferent to them both?

Haruka Shinozaki has been interested in the class representative, Akiho Kousaka, since his first year in high school. She is attractive, good at sports, and is an all-around model student. Since they are in the same class this year, Shinozaki decides to confess his feelings—and, to his shock, Kousaka agrees to be his girlfriend! However, he finds that Kousaka is a bit stranger than he first thought: this seemingly perfect girl has never been in a relationship. But even though she is inexperienced, she vows to please Shinozaki in every way she can... such as learning multiple sex positions or his fetishes. Shinozaki tries to assure her that her studies into such subjects aren't necessary, but Kousaka devotes herself to making him happy in more ways than one. [Written by MAL Rewrite]