I want to say this was weird but...
Yoko Taro things by definitions are weird.

I really wanted to to put a 7/10 but...
But the ending pissed me off so bad, I screaming to myself "WHY" in different language because of the pain I was feeling. I happen to love emotional trauma. 8/10.

(((Spoiler of the ending under this)))
If you read this manga I'm gonna assume you've played Drakengard 3. I loved One from the moment I saw him in the game. I loved his sister, One. I loved them both.And I was eager to know what happened after sister One's death. I really loved this character because It was all I had left after One died. WHY.