Mikan

The academy's head instructor who oversees almost all things related to the school. She is known for her mastery of all things related to becoming a maid or butler and her strict, cold demeanor towards those who slack off in the middle of duty and anything unrelated to school matters and as such, students and even the principal herself avoid provoking her. She uses fountain pens in the same way a ninja uses throwing knives with deadly accuracy.
Source of information: Wikipedia
Voiced by: Kumi Sakuma