My Elf System - Chapter 7 - 0. Third Mission Completed.

The scum’s or villain’s long road of transformation was tentatively set to the world:
The abandonment of the educated youth’s wife (Completed)
The hidden marriage of the scum film emperor (Completed)
The best brother in the world (Completed)
The Phoenix male who destroy the bridge after crossing the river (Completed)
The treasonous general (Completed)
I’m an honest man (Completed)
To become the top scorer in the School of Agriculture (Completed)
The soft rice man’s self-cultivation (Completed)
The whole world is reborn (Completed)
I want to survive on a desert island (Completed)
The stallion male who has seized the opportunity (Completed)
The perverted self-salvation (Completed)
The spring of the loafer (Completed)
The misplaced life (Completed)
The miser career (Completed)
The ghost is out of feeling (Completed)
The Queen’s favorite husband (Completed)
The vicious girl with her godfather (Completed)
I want to be a good person (Completed)
I does not tear up the family (Completed)
The perverted common plant (Completed)
The Mary Sue’s men (Completed)
Every time I was reborn, someone wants to kill me (Completed)
The old people’s counterattack path (Completed)
The global evolution (Completed)
When I became a net red (Completed)
For you, good person (Completed)
His heart had white moonlight (Completed)

- Description from Novelupdates

The handsome Emperor falls in love with a Knightess! Knightess Poliana loses to the Acreian Army and despite her struggles to survive in a male infested military, she is now about to die. But then, the young king of Acreia sees her efforts and tells her: "I have a dream, I wish to conquer the world and become an Emperor, would you like to join me?"

Gu Bailu has transmigrated. She was in Dubai one second ago, but the next thing she knew, she finds herself in a deep, dark forest. To make things worse, her body has been poisoned and s*x is the only antidote. Thinking that she will die in the middle of nowhere, she somehow runs into a handsome guy who’s semi-conscious. Eager to rescue herself, Gu Bailu lies him down, not realizing that he is Prince Zi, a powerful and brutal man who has killed every woman that had approached him. Her life is saved, but she can’t get away from him…

Caught up in a ritual performed by a deity of another world, Eiji Choukai was then transported to another realm. The otherworldly deity responsible of the ritual looked at Eiji’s potential incarnations and quickly pulled out Classes like those from, “I Reincarnated Into a Vending Machine.”

But it seems the Classes available for the average person was not available to him. Only the “Parasite” Class was shown.

Without choice, Eiji grudgingly choose the Parasite Class.

His reincarnation into this new world seemed somewhat despondent, but after using his newfound powers, he suddenly realizes its true potential. It seems he’s able to amplify himself countless times by obtaining the powers of others. This luck of his was too good to be true. Seems his level might rise a little bit too much.