The Black Book: Seven Deadly Sins - Chapter 30: Didn’t My Dao Heart Rise for Nothing?

He Lang died by his own hands for the sake of his imperial younger brother’s ambition, whom he loved. He was offered to be reborn in exchange for giving up his past romantic feelings. Reborn without the burden of his romantic feelings, he brings with him a manual to new worlds. He wholeheartedly followed the instructions of the manual to complete the tasks, not knowing that the originally slag gong was blackening…
He pleaded to his affectionate Emperor brother to release him, he pleaded to the paranoid prisoner next door, but until the end he remained baffled.
In the end, he discovered that the full name of the manual was – “Slag Shou Cultivating Manual”
Σ (っ ° ° °;) っ!

- Description from Novelupdates

Once she crossed through, she actually became the disfavored third WangFei?

A young man finally managed to become an immortal, a powerful cultivator able to lord over millions of souls. He took advantage of his tremendous luck and fortune to become the youngest immortal in history. He now wants to create his own sect and enjoy life, one filled with female disciples!

aira swore she’d keep her heart locked until her final year ended. No distractions. No love. Just goals.But then he walked in—arrogant, mysterious, and dangerously charming.One wrong glance turned into late-night texts. One shared secret became a stolen kiss.And suddenly, the future she’d planned… didn’t seem so clear anymore.Can she graduate without breaking her heart? Or will love ruin everything before the last bell rings?