|Romaji Name||Narumi Yui|
|Date of Birth||October 7|
|Voice Actor||Julie Ann Taylor|
|Drama CD Seiyū||Chiwa Saito|
|Manga Debut||Manga Episode 13|
|Anime Debut||Episode 5|
- "Yoo-hoo! I'm here to hang out with you!"
- ―Yui Narumi
- "Homework, huh? Eh, as long as ya keep it vague, put down whatever you want!"
- ―Yui Narumi
Yui's physique is average. She has a well-rounded face, a large forehead, a catlike smile similar to Konata's and straight and short dark emerald hair. She also wears small glasses.
Yui Narumi is Konata Izumi's cousin and Yutaka Kobayakawa's older sister. She is a very easy going female police officer for the Saitama Prefectural Police Department who acts before thinking. She is a bit of a klutz and is a meganekko. However, she has a tendency to exhibit road rage when she is behind the wheel (but, incidentally, shows incredible skill, as a street racer). This is ironic because she is very carefree when driving and breaks a lot of traffic laws, however she herself is a Traffic Officer. She isn't into fashion that much, and after getting married, Yui left behind her maiden name, Kobayakawa. However, her husband is out of town most of the time during the series, so she frequently visits Konata's house, mainly as a distraction, seeking to play her video games and read her manga. Usually, Yui will come over to Konata's home very late at night while drunk. A running gag in the series is that Nanako Kuroi is oblivious to the fact that Yui is married. She drives a blue Subaru Vivio in the anime.
'[Character song Vol. 012 Kagami Hiiragi features 2 songs by Yui's and Nanako's voice actors, Saori Nishihara and Konomi Maeda. The songs are:
- Kekkon Nantesa Pappayaa (What They Call "Marriage", Pappayaa)
- Tekireiki na Reidi (Marrying age Lady)
- In episode 18, when Konata and her friends play the animal personality game, Konata thinks Yui would be a leopard
|Konata Izumi - Tsukasa Hiiragi - Miyuki Takara - Kagami Hiiragi - Ayano Minegishi - Misao Kusakabe - Yutaka Kobayakawa - Minami Iwasaki - Hiyori Tamura - Patricia Martin|
|Sōjirō Izumi - Kanata Izumi - Yui Narumi - Tadao Hiiragi - Miki Hiiragi - Matsuri Hiiragi - Inori Hiiragi - Yukari Takara - Honoka Iwasaki - Nanako Kuroi - Hikaru Sakuraba - Hinata Miyakawa - Hikage Miyakawa - Akira Kogami|
|Goldy - Cherry|
|Anime Only Characters|
|Minoru Shiraishi - Meito Anizawa - Daisuke Ono - Gotouza|
|Manga Only Characters|
|Kō Yasaka - Yamato Nagamori - Izumi Wakase - Fuyuki Amahara - Tamaki Yamanobe - Miku Busujima|