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Last year, it turned out that their mischief-loving principal forgot to remind the senior sisters, and then Senior Sister Margreta was the first to suggest multiple infections of materials at once to avoid wasting time in case of failure.
She simultaneously infected a whole bag of seeds and a bundle of wand materials.
The other senior sisters did the same, although they were more conservative, at most infecting three sets of materials at the same time.
At first, it was fine, but when the materials were close to being completely infected, they started to fight each other. By the next morning, all their materials had been ruined.
It was only after that the principal smacked his forehead as if just remembering to say, "Spiritual materials infused with a witch's magic power will repel each other, which is why a witch will never have two brooms or two magic wands at the same time."
