Kirino is Kyosuke's 14-year-old younger sister. She is mature for her age with a cold, tsundere-like personality. She has a strong "little sister" fetish and owns many adult games with older brother/little sister themes, which she got a job modeling to pay for. Despite this, she states she does not know why she started liking it, though it is suggested that she has a brother complex and is using the games as a surrogate to this. She often denies such feelings and believes the 2D and 3D worlds should be kept separate.