Kirumi is a refined, mature young lady who's described as "a professional who does a perfect job". She is polite and formal, as well as quite serious, and very willing to use all of her power to cooperate with the other students. She is intelligent, observant, and level-headed. Her intelligence can be shown when she is speculating. Her speculations are provided with a fact and thus they are quite hard to refute.

Here are some voice examples: https://youtu.be/MV_kD7FaiGA