The Protagonist Just Wants to falling Inlove

In each world derived from novels, there would be such a person; a protagonist, who although in name was no less than a proud son of heaven, had a destiny of neverending suffering, humiliation, betrayal, and abuse. The threads of these people's fates were twisted in such a horrid way for one and only one simple reason; in the eyes of heaven, they were people whose temperaments should be honed and flaws smoothed akin to the surfaces of small pebbles fallen under running water, until the day came when they would finally be able to claim the seat at the pinnacle of the world that rightfully belonged to them.
But the harshness of such tempering was unbearable to the protagonists, and by the time they achieved their predestined glory, no residual goodness and kindness remained in their hearts. One by one, those people chose to walk the road of blackening, from which they were never to return.
Then, some systems received a rather strange task; change the destiny of the protagonist, no matter what it takes. This was to be done by (including, but not limited to:) [acting as the protagonist's golden finger], [becoming the protagonist's mentor], [acting as the protagonist's good brother]...
The systems were confident in their success: there should be no problem, we can solve anything.
The protagonists replied: don't worry, we'll take care of anything that goes wrong.