On a rainy night, Soh-yon is summoned to the underground Tohda ponds. There, Soh-yon finds all the Kiba, the Duke's most prized Tohda, dead. Knowing what would happen next, Soh-yon decides to spend the entire day with Erin. But later that night, soldiers come to the house. It was only then that Erin learned that her mother was going to be sentenced to death.
ある夜、アケ村に闘蛇の弔い笛が響き、駆けつけたエリンたちが目にしたのは、キバの死骸だった。キバは大公から預かった最も大切な闘蛇故に、その死は村が取り潰しに遭ってもおかしくないほどの大罪なのだ。