The Tunnel to Summer, the Exit of Goodbyes: Ultramarine (Manga) Vol. 3

YOUR HEART’S DESIRE 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-winning light novel!
Series Overview: Tono Kaoru heard a rumor: The laws of space and time mean nothing to the Urashima Tunnel. If you find it, walk through and you’ll find your heart’s desire on the other side…in exchange for years of your own life. On the night Kaoru just so happens to find himself standing in front of a tunnel that looks suspiciously like the one the rumor describes, he finds himself thinking of Karen, the sister he lost in an accident five years ago. To Kaoru’s surprise, he’s been followed by the new transfer student Anzu Hanaki, who promises to help him 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?