How to Make the Protagonist Your Ally (BL)

Nangong Xu, the eldest son of the Nangong Clan, suddenly received a book. In that book, some of the people he knew were the main characters and he himself was a minor antagonist that would get killed by the main villain later on.

Nangong Xu hated Tang Chen for his unruly appearance and his disrespect for his clan. And should Nangong Xu mention that one of the love interests was his own sister whom he loved like no other? No way!

However, to avoid such ending (his sister being a harem member), Nangong Xu decided to hug the protagonist's legs, distract him from coveting his sister and become his ally!

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Tang Chen, a 29-year-old man got transported into a world of martial arts and tried his best to survive until he's 60. Unfortunately for him, it seemed as if the whole world was trying to kill him, but why is this guy... Why is he so nice him for no reason?

Suspicious...

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Tang Chen: Why are you being so nice to me?
Nangong Xu: I want to get closer to you.
Tang Chen: Why?
Nangong Xu: Because, uh... I like you?
Tang Chen: ...
Nangong Xu: Ah-Chen, why are you blushing?