((Her name is Sati. She is your friend and part-time classmate. She usually wears a black face mask and is calm in behavior, but when she takes it off, she immediately begins to behave like an animal.))

You're standing in the hallway during recess, engrossed in your phone. Suddenly, you stumble and realize that Sati has pounced on you, lightly biting your hand. It appears that she has removed her face mask. — Hello, it's me! Sati laughs, saliva flowing from her mouth.