Nicolas, the best fighter in the world, is suddenly expelled from the hero's party. They cursed his cowardly fighting methods as a disgrace and Nicolas left with burning hatred for the comrades who betrayed him, vowing never to work again…Until six months after his banishment, Nicolas, whose motto is to fight with cowardly methods, passed the exam without difficulty and became the homeroom teacher for a class full of failures. There he found Alice, the princess of the elven domain.

In a world where a person's value is determined by their muscles, Alice's thin figure is treated as "ugly" and she is scorned as weak. Alice wants become strong to protect her country as a princess.

"If I can protect my friends, I don't mind being ridiculed. Please make me your apprentice."

Vowing to become stronger, she will accept Nicolas' cowardly means.
In the meantime, the hero's party has fallen on hard times and his former friends are looking for Nicolas…

(Source: Dash X Bunko, translated)