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!