Tập 13: Riki phát hiện ra Midori, bản sao không bóng của Mio, và gặp phải tình trạng mất trí nhớ về cuộc gặp gỡ tại bãi biển.

13

Riki sees the girl who looks like Mio in the courtyard, but she disappears soon after. Mio remains absent from school for several days, and people around Riki slowly start forgetting about her. The next day, Riki finds Mio in the courtyard, who gives him her treasured book of poems and invites him to go with her to the beach. Midori, the girl who looks like Mio, shows up at the beach and reveals that the reason why Mio always carries a parasol is to hide the fact that she has no shadow. Upon learning this, Riki suffers an attack of narcolepsy, and when he wakes up, he is already back in his dorm room, but cannot remember what happened at the beach. Life returns to normal, until Riki rediscovers Mio's book of poems and goes to look for her in the classroom. However, Midori comes in and everyone except for Riki know her as Mio. While mulling over Mio's disappearance, Midori confronts Riki and wants him to call her Mio like everyone else, which Riki refuses. Midori points out that she also does not have a shadow, and Riki thinks that Midori may be Mio's shadow. Midori says that eventually, he too will forget about Mio. (Source: Wikipedia)