The supporting character's harem is very normal - Chapter 99 Poor Malina

Silas Blackwood wakes up with a machine in his chest – his missing mother's parting gift to help him survive the war with the Fae. This “system” grants him bizarre abilities: neuromancy (magic of the mind), biomancy (magic of the body), and essomancy (magic of souls and essences). Oh, and it fused a leviathan's mana core into his body. Because why not become part sea monster?At Arcanium University, a military boot camp churning out mage knights, Silas finds himself targeted by rich brats who think being born with a silver wand up their ass makes them special. When they leave him for dead, Silas decides it's time to show these spoiled kids what real power looks like.As Silas grows stronger, he discovers he can upgrade himself by absorbing essences from magical beasts and demons. Just when he thinks he's got a handle on things, Silas learns his mother's alive, and now he's got a new mission: a rescue that'll take him and his friends straight into the depths of Hell.

— Climax exorcism.

An obscene ability that forces forces anyone stricken by it to climax, regardless of whether they are living or dead.

As a bonus, it also forces evil spirits and monsters to ascend to heaven.

This is a world where evil spirits and monsters are everywhere and being an exorcist is a real job.

Talented boys and girls with bright futures are trained at the “School for Exorcists”.

Furuya Haruhisa is a boy cursed with the ability, climax exorcism, and is also the school dunce.

Using the ability could lead to his own social death…

But then, Haruhisa met her.

Misaki Soya, a girl possessing a similarly cursed pair of eyes — demon eyes.

And so begins the legend of how history’s worst exorcists came to be known as the strongest before anyone realized it. Their first official job results in a grand performance with a monster woman who runs away from boobs.

— Nhoooooo!?

A coquettish voice echoes throughout the neighborhood tonight.

It is undoubtedly evidence of an ascension.

Are those useless exorcists using their obscene abilities?

Is ero going to save the world?

A slightly ecchi exorcism performance!!

Working in a big factory for several years, Wang An, who was prematurely aging, accidentally obtained a cheat that can earn experience. The improvement of his skills brought him unexpected surprises.

It turns out that some things are not just legends.

Lightness kung fu can really make people walk on the snow without a trace, and fly over the walls.

Vajra is not broken, it can indeed produce the power of vajra, and become the body of vajra, invulnerable to swords and guns.

Congenital qi, grasping iron into mud

 …

Brushing experience does not rely on simple repetition, but requires continuous learning, summarization, and comprehension.

- Description from novelbuddy

Riding out the apocalypse on a tropical island isn't exactly a vacation. When mana arrives on Earth, Coop finds himself isolated in paradise with only one real option to survive. He needs to claim a civilization shard and level up. Coop maximizes his chances by carefully selecting a class and committing to progression. He’ll need to grind thousands of monsters to compete on the system's leaderboards while upgrading his settlement to represent the factionless.