As Keita tries to study, Ako and Riko compete with each other to be the most helpful. Whilst alone in the room, Riko and Keita end up doing some 'footplay' under the kotatsu until Ako catches on. Whilst looking up on good luck charms to help Keita with his studies, Ako and Riko learn of one that is made using pubic hairs. After much deliberation, the sisters pluck their own hairs to make the charm and give it to Keita, convincing him not to look inside. Keita takes it to school with him, though Ako and Riko are understandably embarrassed.
Como Keita trata de estudiar, Ako y Riko compiten entre sí para ser el más útil. Si bien solo en la habitación, Riko y Keita terminan participando en 'Footplay' bajo el kotatsu hasta Ako capturas. Si bien la investigación de buena suerte para ayudar a Keita con sus estudios, Ako y Riko aprenden de uno que se hace uso de vello púbico.
여름이 지나고 순식간에 가을이 되었다. 수험을 눈앞에 둔 케이타를 위해 아코, 리코는 손수 부적을 만들기로 한다. 하지만 그 부적의 내용물이란…?
