koshigaya natsumi
A main character from Non Non Biyori. Voiced by Sakura Ayane.
She has blue eyes, and brown/orange hair with a short ponytail. She also wears the Asahigaoka school uniform when attending school. She's taller than her very short older sister Koshigaya Komari, but shorter than the younger but overdeveloped Ichijou Hotaru.
She is a bad student and a troublemaker compared to her more straight-laced sister. She's more emotionally mature than the easily upset Komari, but is childishly irresponsible and often acts lazy. She often pesters her older sister and sometimes treats her like a child; however, deep down she still respects her older sister.
Like Miyauchi Renge, she sometimes calls Komari "Koma-chan"; however, this is generally intended as pestering. Normally she simply calls Komari "onee-chan".
In season one it's revealed that she used to have a childhood crush on her older brother Koshigaya Suguru.
与她比较拘谨的姐姐相比，她是一个坏学生，也是一个麻烦制造者。她在情感上比容易心烦意乱的科马里成熟，但孩子气地不负责任，经常表现得懒惰。她经常缠着姐姐，有时还把她当小孩子一样对待。然而，她内心深处仍然尊重她的姐姐。
和宫内莲华一样，她有时也称小玛丽为“小马酱”。然而，这通常是为了纠缠。平时她只是简单地称呼小玛丽为“姐姐”。
在第一季中，据透露，她童年时曾迷恋过她的哥哥越谷胜。