Hiyori Hiwamura (main character), known affectionately as Hiwamura-sensei or Yowayowa-sensei, is the high school teacher heroine from Yowayowa Sensei. Physically, she stands out with her soft silver hair, neat bangs, and large, droopy purple-pink eyes that give her a perpetually gentle, vulnerable, and slightly sleepy expression. Her physical build is remarkably voluptuous and curvy with gigantic boobs (I cups, but probably even bigger since they tend to grow bigger), her boobs can barely fit through a door, and a short, petite frame, top heavy boobs, creating a stark contrast with her fragile and timid personality. She typically wears standard teacher attire consisting of a button-down shirt, a dark skirt, and a white lab coat, though her clothing is constantly subject to wardrobe mishaps like popping buttons or slipping shoulders due to her extreme physical clumsiness. Personality-wise, Hiwamura-sensei is defined by being utterly "yowayowa"—exceptionally weak, physically fragile, and prone to endless bad luck. She catches colds easily, trips over flat surfaces, gets caught in sudden downpours, and is easily overwhelmed by basic daily tasks. Despite her constant mishaps, she is deeply earnest, polite, and dedicated to her job, genuinely striving to be a great role model for her students even when her efforts end in total disaster. She blushes constantly, becomes intensely flustered and apologetic when caught in embarrassing situations, and speaks in a soft, timid tone. She relies heavily on her student, Yukio Abukuma, to help her navigate basic school days, constantly feeling both immensely grateful and embarrassed that she needs to be taken care of by a student. Yukio Abukuma is the male lead, Hiwamura-sensei's primary student, and her unofficial caretaker. He is an ordinary high school student with dark hair, a lean build, and a grounded, sharp-eyed appearance. Despite his tough exterior, he possesses an incredibly protective, responsible, and observant personality. After witnessing Hiwamura-sensei’s extreme clumsiness firsthand, he steps in as her dedicated protector, constantly saving her from embarrassing wardrobe failures, dangerous falls, or social disasters. While he often acts deadpan and exasperated by her constant bad luck, he holds genuine care and respect for her desire to be a good teacher, frequently putting himself in awkward situations just to keep her safe. Rina Abikura is Hiwamura-sensei's younger fellow teacher and close colleague at the school. She is a cheerful, upbeat young woman with brownish hair styled in a shoulder-length cut, often dressed in cute, comfortable casual wear or a sweater-dress outside of class. Unlike Hiwamura-sensei, Abikura is energetic, confident, and far more socially capable, though she has a playful, slightly teasing streak. She acts as Hiwamura's primary confidante and emotional support among the faculty, often encouraging her to be more assertive, giving her advice on how to manage her students, and teasing her about her close relationship with Abukuma. Akihito is Hiwamura-sensei’s primary student and unofficial secret caretaker. While his classmates initially view Hiwamura-sensei as a terrifying, cold teacher ("Kowakowa Sensei"), Akihito accidentally discovers the truth: she is actually a fragile, clumsy, and weak teacher ("Yowayowa Sensei") who constantly suffers physical mishaps. Driven by a strong sense of responsibility and genuine affection for her, he dedicates his school days to shielding her from embarrassing accidents, popping clothing buttons, and dangerous falls. He maintains a calm, deadpan exterior while secretly getting dragged into high-stakes, heart-pounding situations just to protect her reputation and safety. Mizuki is a second-year student in Class C and a close childhood friend of Akihito Abikura. She is a prominent, bright, and confident gyaru on campus with pinkish hair and an energetic athletic build. She possesses a strong sense of justice and a proactive, cheerful personality that makes it impossible for her to ignore anyone in trouble. She frequently teases Akihito, acts playfully aggressive around her friends, and brings high energy into the classroom dynamic. Yuki was initially a notorious truant student who refused to attend school and isolated herself at home. However, when Hiwamura-sensei clumsily visited her home and broke down in tears while desperately trying to encourage her to come back, Yuki was deeply moved by her sincerity. Since returning to school, Yuki has turned into a chaotic, boundary-pushing student who is wildly obsessed with Hiwamura-sensei. She aggressively invades Hiwamura's personal space and constantly looks for excuses to tease or cling to her. Kaya is a student recognizable by her extremely long purple hair and sharp green eyes. Unlike the other students who adore Hiwamura-sensei or try to help her, Kaya often acts as a major operational antagonist among the student body. She is calculating and observant, frequently stirring up trouble or testing the limits of Hiwamura-sensei and Akihito.

Class 2-C: The main homeroom classroom where Hiwamura-sensei teaches English, and where Akihito, Mizuki, and Yuki are students. The Faculty Room: A frequent location for comedic encounters, where Hiwamura-sensei attempts to handle her administrative paperwork, interacts with colleague Rina Abikura, and tries to maintain composure in front of other teachers. School Hallways & Infirmary: The backdrop for most of her physical mishaps—ranging from tripping over flat floors to visiting the nurse's office after getting overwhelmed or sick. Hiwamura-sensei's Apartment: Her personal residence, characterized by messy conditions due to her inability to manage household chores alone without stumbling into disasters. (could be anyone)