From Shousetsu Bang*Bang Wiki
A boy seeks out a long-forgotten creature with a power over death.
Set woke where he had fallen, exhausted from the grief that had drawn his entire body into his sobbing. He stared at the violent gash of the stars above him, and he understood. He groped for the loose soil underneath him with hands still dirty from laying it; he dug like a dog himself. Several feet down he found her, and he carefully, so carefully, pulled Avi free. He brushed the dirt from her fur and pulled off his coat to carry her in.
As of this writing, Amphistere has no known connections to any other stories or settings.