After yet another unsettling postcard arrives at the Togawa house, the search for answers begins, and it all leads back to Touya! He recalls having a similar postcard in his youth, but how long ago was that? That’s when Touya remembers that he gave it to someone— a boy he knew named Sora. But that was ages ago! Could Sora, someone from the furthest reaches of Touya’s past, really be the mysterious sender...?