Main character of the story.
A 20 years old university student that lives in a dorm. His birthday is September 4, blood type O and his height is 166cm. He's super masochist and his signature phrase is "Please cuss me". His love interest is someone accepts himself as a masochist.
He loves pasta and he dislikes beans.
He has a younger sister named "Miyoku" and older brother which Kei and Miyoku calls him "Tou-nii". (Real name not yet revealed)
(Source: Japanese Wikipedia)