Riki is resolute that he will not forget about Mio, but Midori plays around with his memories of her, leaving him unsure about how much of his memories of her are real. Riki seeks help from Kyousuke, but all he can offer is to tell Riki to not trust anyone but himself for the sake of Mio. Riki suddenly remembers Mio saying she was going to submit a tanka in the school’s competition, and discovers that the poem is about the conversation they previously had about the paper airplane. After talking with Midori, Riki realizes Mio is at the beach, where the two reunite. Mio tells Riki how she first “met” Midori as a child, who is in fact an imaginary little sister she created. Mio’s mother eventually gets her medical treatment until she finally forgets all about Midori. However, she remembered her after reading the tanka by Bokusui Wakayama about the bird and the ocean, which caused her to black out. After she came to, she realized her shadow was gone.