MTL - Strange Life of a Cat - Chapter 280 Crooked idea

Kirby Jon transmigrates to a parallel spacetime and is chosen to act as a bank robber in an exercise. Kirby Jon, who has obtained the God-level acting system, would receive a generous reward if he can act as a robber and attain an S-level score.

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

He was a wealthy and mysterious financial backer who had appeared before her when she needed money the most. After the courtship, she took the money and left.

The story is about a boy entering high school, who answers a strange call from a public phone one night. The caller challenges him to a bet: She’ll remove the birthmark which he sees as the cause of so many problems, and he’ll have fifty days to win the heart of a girl he’d considered far beyond his reach. And with this, a very strange summer begins.