The Reincarnated Assassin is a Genius Swordsman - Chapter 15

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

Sixteen years after transmigrating into the world of cultivation, Lu Yi’s long-lost cheat finally awakened. The cheat was a simple task panel where one could earn various rewards by accepting and completing tasks. Lu Yi was surprised to find that he could publish tasks for himself and complete them for rewards. So Lu Yi embarked on the path of self-publishing tasks for himself. He published a task for himself to “practice the Divine Sword technique ten times,” and upon completion, his level in the Divine Sword technique increased by one. He published a task for himself to “defeat an outer disciple,” and upon completion, he obtained a precious Perfect Qi Condensation Pill. He published a task for himself to “break through to the Foundation Establishment Realm,” and upon completion, he obtained a top-grade magical weapon. Without realizing it, Lu Yi found that even becoming a saint or ancestor seemed easy with this system.

It’s a story about a man who got transported into a novel and possessed a slum boy. He met a noble girl and served her as a butler for 13 Years. Now the girl has already fallen from her noble life and lives in an abandoned mansion with paralyzed legs. Why did she become like that? Of course because she is the villainess in the novel.