"Let's meet at the place where it all began." The true plot is revealed as Takuru travels to the Hikariwo. There he eets the other person behind the series of brutal killings.  But a deeper mystery lurks in the background: what Serika is telling him doesn't make sense, and he's convinced that as horrible as the story is, there's more to it than even he knows.
If I deal with you, I can 
go back to my research.
إذا تولّيتُ أمرك أستطيع العودة إلى بحثي
Wenn ich mit dir fertig bin, kann ich mich
wieder an meine Forschungen machen.
Si me encargo de ti, podré volver
a centrarme en la investigación.
Si me encargo de ti, podré volver
a centrarme en la investigación.
quand j’en aurai fini avec toi,
je reprendrai mes recherches.
Se ti sistemo, potrò tornare alle mie ricerche.
Posso voltar para a minha pesquisa
 depois de cuidar de você.