TV-Series
Description
Natsu Ichijō is a student at Keimon West Private High School, hailing from a wealthy and distinguished family. She has green eyes and blonde shoulder-length hair, standing at an average height of 1.60 meters with body measurements of 87 cm bust, 60 cm waist, and 86 cm hips. Her typical attire is the school uniform: a long-sleeved white blouse, red bow tie, red short suspender skirt with white stripes, black knee-high socks, brown shoes, and a pink and black headband. For gymnastics, she wears a white and red V-neck shirt with red underwear; for swim class, a blue one-piece swimsuit with white or orange stripes; and for sleepwear, light blue shorts with a light blue jacket and a pink bowtie headband.

Her personality is cheerful and calm, yet she lacks self-reliance and often depends on friends for assistance, a trait stemming from her sheltered upbringing where even simple tasks were handled by others. She exhibits possessiveness, accustomed to obtaining what she desires, and cannot sleep unless accompanied by someone.

Her background includes an initial arrangement to marry a man twenty years her senior for her father's business interests, but both the intended husband and her father died five years prior due to the MK virus. This led her to enroll in Keimon West Private High School due to her interest in Shōta Doi, one of the few males immune to the virus.

She interacts predominantly with Shōta Doi and other classmates, actively competing for his attention and participating in events to spend time with him. She stayed in his dormitory for a week when the female dormitories had broken air conditioning, during which she revealed personal details like a scar on her buttocks from childhood, though the cause remains unknown. She and Shōta engaged in sexual activity, and she expressed happiness about their growing closeness. She also participated in group activities with other females involving Shōta, such as in the school infirmary and public baths.

She was involved in key events including the terrorist attack on the school, after which she visited Shōta in the hospital. She was later relocated to a mating facility with Shōta and others, where she learned about the existence of four other immune males globally. Throughout these events, she maintained relationships with classmates like Akira Tōdō and Shunka Hiiragi, engaging in group interactions and activities.