The story begins with Tatsuya Endo, a high school student, discovering he can see "Status" windows for himself and others after a bout of chuunibyou. This ability reveals details like name, age, race, stats, and even relationship status and specific conditions like "virgin" or "pregnant." He first tests this on his younger sister, Saori, and is shocked to see she has a boyfriend, Sato Kenya.
Tatsuya's ability continues to manifest as he walks to school, allowing him to see the statuses of people and even animals, like the dog Kotaro. He observes his classmates, noting that most are "virgins" or "virgins," with a few exceptions. He is particularly surprised by the playboy Kaido Senichi, who is listed as a "virgin" but has a girlfriend. The most shocking revelation comes when he checks the status of the beautiful Kataoka Saki, who is listed as "pregnant: 3 days" and has "servants: 5." This drastically alters his perception of her.
His attention then turns to Takahashi Megumi, the class representative, whose status reveals her to be a "Succubus" with incredibly high stats. Megumi notices Tatsuya staring and approaches him, asking for a school form. Tatsuya's mouth moves on its own, making an excuse for forgetting it, and Megumi, after a moment of surprise, hands him the form and tells him to bring it back by the end of the day, hinting that he saw something.
During lunch, Tatsuya visits the library to research "Succubi" in a book titled "Monster Encyclopedia." He learns about their nature as demons who extract semen from men and impregnate women. The librarian, Negishi Kanae, a former advisor of the now-disbanded tabletop gaming club, startles him. While looking at the book, Tatsuya cuts his finger, and Kanae instinctively licks the wound to clean it, a display that, to Tatsuya's mind, resembles a sexual act, further blurring the lines between medical necessity and his current perceptions.
Later, Tatsuya meets Megumi after school. He returns the form, and she asks for his help organizing materials in the social studies preparation room. Once inside, the door is locked, and Tatsuya realizes he is alone with Megumi, a situation that unnerves him given her superior physical strength. Megumi then reveals that she knows he saw her status as a Succubus and asks if he saw something else. She confesses to a bizarre ritual involving writing a lover's name on underwear and being seen by them for mutual affection. Tatsuya realizes she manipulated him that morning and that she believes he saw her name written on his underwear. After some hesitation, Tatsuya admits he saw her status as a Succubus. Megumi, initially pale, then becomes flustered and pleads with him not to tell anyone. Tatsuya, not intending to reveal her secret, agrees. Megumi, relieved, then asks if she can show him her underwear with his name on it.
The narrative then shifts to Megumi's perspective, revealing her childhood encounter with a powerful blonde girl who inspired her. She explains the school's strange tradition of writing a crush's name on underwear, which she herself has done with Tatsuya's name.
The next day, Tatsuya and Megumi are dating. Tatsuya's friend, Tanaka, questions him about it. Tatsuya confirms their relationship, though he sees Tanaka's boastful status about his girlfriend is false. Megumi arrives, and her status confirms her as a Succubus with Tatsuya as her lover. They go to the social studies room for lunch, where Megumi uses her "Time Isolation" ability to slow down time. She reveals her father is an Incubus with four wives, and she desires a similar family structure. Tatsuya learns that other girls at school also have his name on their underwear. Megumi then shows Tatsuya her underwear with his name on it, and after a kiss, they engage in intimacy.
Later, Tatsuya and Megumi are with Shindo Yoko, a girl who is a "Demon" with immense physical strength. Yoko is carrying heavy boxes and her skirt gets caught, revealing her underwear. Tatsuya and Megumi help her, and Megumi uses her "Manipulative Eye" ability to control Yoko. They discover Yoko's immense strength is due to her being a Demon and that she is being pursued by weightlifting clubs. Tatsuya suggests forming a tabletop gaming club as a cover for discussing their supernatural abilities. Yoko, touched by Tatsuya's consideration, agrees to be his lover, alongside Megumi, as part of Megumi's "harem" plan.
The story then focuses on Yoko's severe menstrual pain. Megumi suggests she visit her home for treatment, as her mother is a gynecologist. At Megumi's home, Yoko meets Megumi's second mother, Orie, who is surprisingly young. Orie discusses Megumi's desire for a harem and reassures Yoko that she is not being forced. Yoko admits she enjoys her relationships with Tatsuya and Megumi. Megumi's fourth mother, Akemi, who can transform into a cat, also appears and bombards Yoko with questions about her relationship with Tatsuya and her appearance. Akemi reveals that many supernatural beings exist in society, including Demons like Yoko, Incubuses, vampires, and snow women. After a medical examination, Yoko is prescribed medication for her pain. Megumi reveals she hasn't started menstruating yet, as Succubi mature later. The chapter ends with Akemi, in her cat form, stealing Yoko's underwear, leading to further comedic chaos.
