The Wrong Way to Use Healing Magic - Chapter 38Vol 17.

His name was Brayden Neal, and he was an ordinary citizen. At eighteen years old, he was bestowed the title of a king!

After ten years of fighting in the northern borders outside the kingdom, he finally returned home. He swore to kill three people the moment he arrived at the capital…

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

Lin Sui transmigrated into the cannon fodder of a cultivation text, a cannon fodder with a human cauldron constitution, destined to be a servant. Lin Sui, unwilling to resign himself to it, seduced the Son of Heaven, but when the cut out his Dao bone and transferred it to himself, the Heavenly Law struck him down.

That Dao bone in his body became the System that restrained him, issuing the order: You must retrieve all of his soul, serve him as your master in every world, and spare no effort for him until your dying day!

Lin Su was all smiles as he agreed, but all his life, the thing he loathed most was others telling him what to do.

Therefore…

In the first world, he was an arrogant and domineering, rich and powerful Young Master, while the other person was a pitiful and humble illegitimate child.

He humiliated him by saying he was only fit to carry his shoes, and spoke words of love next to his ear when the noise of the crowd boiled over.

System: You motherxxxxxx [beep——]

Lin Sui, innocently: Aren’t I serving him as my master?

In the second world, he was a newly-promoted top talent in the entertainment industry, while the other person was a former Best Actor who went silent after an accident.

He ridiculed and suppressed him, saying deserved to make a comeback even if he was past his prime, and kissed the scars on his body at night, leaving resources behind to gracefully leave afterwards.

System: [beep——]

Lin Sui, spreading his hands: Am I still not sparing enough effort?

In the third world, he was an S-rank Alpha, while the other person was a mentally-damaged former SSS-rank Alpha.

He looked down on him, saying that useless people also deserved to get back on the battlefield, and when no one was around he said ‘since you can’t smell pheromones, then I will be your omega’, and almost lost his life giving himself to the other person.

System: …..

Lin Sui, smiling: Is my dying day enough?

Even though, in the end, he was tucked away in a golden house by the wealthy upstart, captured by the triple gold Best Actor, and completely embraced by the Imperial Marshal, he was still happy.

System, weeping bitter tears: Big brother, I’m begging you, I won’t tell you what to do any more!

- Description from Novelupdates

After accidentally falling, she actually finds herself bound to a Second Female Lead Counter Attacking System!