Natsumi Tsujimoto (辻本 夏実 Tsujimoto Natsumi?) is a fictional character and the main protagonist in the You're Under Arrest franchise. Her Japanese seiyu was portrayed by Sakiko Tamagawa and her English voice by Tamara Burnham Mercer. In the Live Action version, she was portrayed by actress Misaki Ito.
Natsumi is an officer stationed at the fictional Bokuto Station in Tokyo's Sumida Ward. She is very outgoing as well as very laid back. She often demonstrates superhuman strength second only to Shoji Tokairin and is a motorcycle enthusiast, capable of high-risk maneuvers on both bikes and mopeds. Natsumi has a prodigious appetite for food and alcohol, and has been known to show up at work with a hangover. She is also a chronic late sleeper. Despite having many bad habits, she is a very capable police officer and does her job seriously when needed. She keeps a mini-moped, a Honda Motocompo (JR-2) in Miyuki's Honda Today squad car and uses it when a flanking strategy is required. It is prominently labeled "NATUMI" (in the Nihon-shiki transliteration system) before her first day at Bokuto in the beginning of the first anime, later re-coloured and re-labeled "POLICE" in the later appearances and on the Bandai Model kit of the Honda Today. When off-duty, she operates a Yamaha RZV motorbike until it is damaged beyond repair during later part of the first season. She is subsequently tricked into buying a Subaru R-2, which is in a near-non-functioning state. This car is then thoroughly renovated and heavily modified by Miyuki into a patrol car. She uses the wrecked motorbike's engine, modifying the car to make its operation follow closely to that of a motorbike. In the manga version, this car operates with double engines.
Natsumi is also familiar with judo and kendo, being able to defeat her opponents during training sessions. Her strength and her familiarity with hand-to-hand combat complement Miyuki's brilliant mind in creating devices or modifying known vehicles very well, making her and Miyuki famous throughout Bokuto Station. She is also the only person in this series able to consistently defeat Strikeman's fastballs and is called Home-Run Woman by Strikeman for this very reason.
According to the information in the You're Under Arrest series, Natsumi was born on August 12, 1975. Not much information is revealed in the story, though she had lived in Asakusa before enrolling in the Metropolitan Police Department Academy and became classmates with Miyuki Kobayakawa before being dispatched elsewhere in the Greater Tokyo Area .
The two eventually met by accident when Natsumi was late for work during her first day on duty with the Bokuto Station. She was partnered with Miyuki for a number of years. But for a short time, Natsumi was scouted by Tokyo Metropolitan Police Department Headquarters to be part of a prototype female motorbike unit before declining an invitation to train further with them . She was known to be infatuated with Detective Tokuno and the Kachou of the Traffic Division before meeting Shoji Tokairin, who became her rival and love interest . Natsumi and Miyuki, later on in the series, broke the back of a car smuggling syndicate that operated by stealing luxury vehicles, leading to the group's disbanding. Due to her actions, Assistant Kaoruko Kinoshita moved her to the Tokyo Metropolitan Police Department with Miyuki as part of her specialized training program in enhancing officer's skills related to police work . During the Hachi-Ichi-Go crisis (Bee Number One in the dub of You're Under Arrest: The Movie), she and Miyuki proved themselves as law enforcers when they apprehended renegade police officer Tadashi Emoto as he tried to commit suicide by trying to jump from the top floors of the Tokyo Tower. She was also sent to Los Angeles in the United States with Miyuki as part of a foreign officer exchange program with the Los Angeles Police Department .
At the end of the series, Natsumi is recruited to serve in the Special Assault Team and was an operative stationed with the Tokyo Metropolitan Police Department branch. Her partnership with Miyuki and subsequent transfer to the Special Assault Team had then ended nearly on bad terms, almost destroying their friendship until coming to terms with reality . She was replaced in Bokuto Station by Saori Saga, an ex-student who she and Miyuki saved during her police officer days before Saori was dispatched to the said station .
She had been temporarily been at Bokuto again before being transferred out to be trained under the JGSDF's Ranger Platoon before being reassigned again to Bokuto Station, serving as Miyuki's 3rd partner after Saori had left Bokuto to be relocated in another station. 
- A character that is parodied after Natsumi is shown in the first episode of Full Metal Panic? Fumoffu. She is depicted as a wild policewoman who chases the two main character in a police car. Though, in YUA, Miyuki is the car driver of the duo, not Natsumi.
- Common nickname by Strikeman.
- Provided by Natsumi Tsujimoto fan-compiled profile Retrieved on December 9, 2007
- See Episode 4, OVA.
- In the manga, Tokairin doesn't exist and instead, Natsumi was infatuated with Detective Tokuno and the Kachou. In the Drama version, her love interest was Detective Shunsuke Okabayashi.
- In the movie, it is revealed by Natsumi after her first day back in Bokuto Station that she was deployed in the MPD's Traffic Bureau.
- As depicted in the "No Mercy" OVA special.
- See Season 2, Episode 22: A Dissolution of Partnership!?.
- See Season 2, Episode 24: To Each His Own Way.
- See Season 2, Episode 25: The Bridge Built For Tomorrow
- See Full Throttle, Episode 1: Intense Chase Prologue.