Village Daughter of a Potato Farmer, Until She Was Praised as a Sword God

I, Tremina, was an ordinary village girl. No, maybe less than ordinary. I was said to be easy-going for a long time, and I was not good at any form of exercise. At a young age, I decided to take over my family’s potato farm.
With that involved, I was able to enroll in a knight training school.
There, I discovered a great talent of mine, aided by my gentleness and overwhelmingly strong mental strength.
Anyway, I was able to forge mana without feeling tired at all. Mana is the source of life and power, and if an ordinary person trains with it for two hours a day, they will, naturally, be completely exhausted. But I was able to go on and on for hours and I never got tired. By the way, except when sleeping, Mana can be trained in parallel to doing anything else like eating or studying.
This story is a record of my battle. While being feared as a monster by those around me, I eventually became a sword god with the greatest fighting potential of mankind.
In addition, I also grow potatoes as a side job.