However, these were trivial matters he didn't have to care about. After a brief pause, just as the two were about to run again, he continued.
"And one more thing, your 'Ness Waterless Cleaning Technique' has improved a lot, but it still has some flaws.
Next time, you can try to fuse it with purification spells, and ensure to clean substances other than liquids too, as evaporating the liquid often doesn't mean there's no residue."
His earnest guidance made the two flush with embarrassment.
Because this spell was the one they just used to clean the "battlefield", reflecting on the teacher's remarks about its defects, didn't it mean all traces had already been discovered...
They stammered for a while.
"Ah, ah, yes, yes, teacher! We, we will pay attention to improving it..."
"Very well, remember to write a paper and submit it to me after completion, and I'll apply for extra credits for you."
