MTL - Your Teacher I, am Hella Rich - Chapter 14

Riku Barusak is a hard-working child. Despite possessing an innate superior physical strength and having withstood harsh training she fails to unlock her talent as a spiritualist. The failure results in her being thrown away by her family.

Abandoned, the only ones that extended a hand to her were the demons, the greatest enemies of the human race. Serving under them as a soldier she becomes a weapon of human slaughter, a fiend that should never have existed.

Being given a chance and reincarnated is nice and all, yet why do I have to become that male friend who just watches the protagonist flirting with his harem?---World: Kaguya-sama: Love Is War - Hyouka ----

Long ago a great calamity struck the earth, destroying much of it and merging what remained with pieces of other worlds.

With these worlds came Aether, a new form of energy that can allow one to transcend the bounds of normal mortality and human limitations.

In a world where humans absorb the essence of aether beasts to gain power, Aiden Hawke joins the class of humans known as arcanists, people who defeat aether beasts and absorb their essence into cores they forge within themselves, and who infuse themselves with the aether that permeates the world around them to increase the power of their body and mind.

However, unlike most, Aiden will find that he holds a unique gift and that his journey as an arcanist will not be so simple.

My Beautiful Teacher tells the story of a university graduate Qin Chao who can’t seem to find a job and is in a downward spiral in his life. Then one night as he walks home from another failed job interview, a vase hits his head, making him get possessed by an old and powerful evil spirit sealed in that vase and following another incidents, inadvertently saved a mysterious university teacher Su Ji, thereby opening his path to cultivation, he also manages to get a job as a security guard at Guangyuan School. A series of adventures then took place as he deals with all kinds of supernatural beings.

- Description from Novelupdates