Mochizuki Kumi

The protagonist's bodyguard, she is always nearby secretly following him. Because the protagonist is both useless and is always getting himself in dangerous situations, she can't help but express her annoyance at him. She has a very harsh tongue, once she opens her mouth, complaints won't stop coming out. But she in fact isn't malicious, the protagonist knew that she says these stuff because she is worried about him, and he trusts her.