Kaoru heard a rumor: The laws of space and time mean nothing to the Urashima Tunnel. If you find it, walk through and your heart's desire will be on the other side...in exchange for years of your own life. The new transfer student Anzu promises to help Kaoru experiment with the mysterious tunnel--but what does she want from Kaoru in exchange? And what will he have left to give, after the tunnel's done with him?

Kaoru and Anzu have joined forces to study the mysterious Urashima Tunnel, which is rumored to give you your heart's desire--in exchange for years of your life. As they explore, connected by a length of string, the two students discover other connections in their everyday lives, including seeing a new side of Kawasaki, the school's arrogant queen bee.

According to an urban legend, there is a tunnel where you can get anything you desire in exchange for your youth--the Urashima Tunnel. Kaoru and Anzu take advantage of their summer break to launch an in-depth investigation of the tunnel, with disappointing results. Kaoru is about to head home when Anzu suddenly invites him to her place. Kaoru's nervous, and Anzu finally tries to express her feelings: "T-Tono-kun, I..."The third volume of the manga adaptation of the popular and award-winnin...

Kaoru learns that Anzu has been assigned a manga editor. While this a big step towards fulfilling her childhood dream of becoming a manga artist, Anzu isn’t happy about it. Kaoru tells Anzu--who is still uncertain whether to enter the tunnel or not--that they should postpone their search. Then he makes a decision: "Well... shall we?" What does Kaoru see at the end of the tunnel? All secrets are finally revealed in the conclusion of this bittersweet tale of mysteries and summer love, based ...