In this chapter, Kaoru Tono waits for Anzu at the Urashima Tunnel, feeling frustrated when she arrives late. Anzu has a plan involving a spool of nylon rope to help them discover the boundary where time distorts inside the tunnel. Excited by the experiment, Anzu is determined to reveal the mysteries of the tunnel, despite Tono's concerns about the potential dangers. Their discussions emphasize themes of risk-taking versus caution, as well as Anzu's bold personality compared to Tono's more cautious nature.
As they run the experiment, Tono enters the tunnel, and after some initial excitement, he realizes that Anzu is deeply invested in this exploration of time and identity. Their friendship grows as Anzu notes Tono's interesting perspective, and they delve into deeper philosophical discussions about what it means to be ordinary versus extraordinary. Anzu expresses her desire to be remembered and to live a life that leaves a mark on the world, contrasting with Tono's simpler view of life's value.
When Tono runs back from the tunnel, he experiences a time distortion, realizing he has been gone for days. Anzu is upset, clinging to a stack of mysterious papers she picked up in the tunnel. However, she hides their significance from Tono, revealing her emotional turmoil. This moment highlights Anzu's struggles and opens a pathway for deeper understanding between the two characters, questioning the motivations behind their ventures into the unknown.
The chapter concludes with Tono contemplating the darker implications of their exploration of the tunnel and the wishes it might grant. It sets a tone of suspense for the adventure ahead, as they wonder what dangers might lie within, as well as the emotional stakes they are facing individually.