- Anata mo kyou de Koishi-chan ni (issho ni onegaishimasu!) Koishichau~!!! Watashi datte migakeba hoseki ni nareru yo! Hyogo-ken kara kimashita! Koishi Kumiko desu!
- Today you will (All together please!) fall in love~!!! with Koishi-chan, too! If I can become polished, I can even turn into a jewel! I came from Hyogo prefecture! I'm Koishi Kumiko!
- E4 (Te wo Tsunaginagara)
- Wimbledon e Tsuretette
- Debuted on September 22, at the AKB48 Group Draft Kaigi 2013
- Hobbies: Travelling, shopping, Listening to music
- Favorite food: Pudding
- Favorite phrase: From a pebble to a jewel!
- Special skill: Cooking
- Future ambition: To enter Senbatsu
- Light Stick Colors: Pink, White
- Known for her high-pitched voice which doesn’t match her looks and special “voice percussion” (rap) she does during MCs, mostly aiming insults at her fellow teammates
- Enjoys making puns with her name, Koishi (Pebble)
- Aspires to be like Takahashi Minami
- Team E's 1st choice at the Draft
- First draft member to perform a full stage show