The comic starts with the protagonist trying to get revenge on his sister's murderers.
It was only in chapter 12 when you have a proper flashback on what happened to the sister.
She has her hands tied behind her back, gagged and ankles tied together.
But since this is just a flashback, she dies afterwards when trying to escape.
A bad end DID scene.
Yoru Ni Naru To Boku Wa Chapter 12
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