Secrets of the Silent Witch, Vol. 4 (Manga)

When a trading company visits Serendia Academy to deliver materials, Monica goes with Elliott to greet them, but a small mistake in the company emblem tips her off to the fact that these men are up to no good. Her suspicion prompts the intruders to attack--and just as things start spinning out of control, a new friend swoops in to save the day! Monica can't breathe a sigh of relief just yet, though. Not when even more daunting challenges--ballroom dancing and tea party lessons--lurk just around the corner!