Extraordinary – Ordinary – Soap!

Lucia Arca, 16 years old. I am the prime representative of all things ordinary, but by using the shabby magical incantation “Soap!” I can only cause soap bubbles to appear. Through this, I perform the duties of a laundry girl employed by the royal castle.
I thought that this magic’s only effect was to clean dirt off from the washing. However, one day I found out it also has the additional effect of purifying monsters. And y’know, because of this it’s turned into a total disaster.
The Heavenly Crystal Trees acts as the intermediary of all magic, and they are also the root of the monster outbreak.
As I’m suddenly forced to accompany the journey to purify the Heavenly Crystal Tree, the companions joining me include His Highness the crown prince, a saint summoned from another world, the commander of the strongest knight brigade and his adjutant, the Dragonslayer Hero, the Academia institute’s top sorcerer, etc. etc. etc. With all the extraordinary people gathering together, I’m going to feel faint! I’m only ordinary!
Surrounded by these prodigies, once the Heavenly Crystal Trees’ purification safely ends, my daily life will return to normal. Right…?