Also known as: 臥煙伊豆湖
Gaen Izuko is a mentor and leader of sorts to the other "oddity" specialists in the Monogatari series: Oshino Meme, Kaiki Deishuu, Kagenui Yozuru, and Teori Tadatsuru, who also comprised her "Occult Research Club" in college. She has a reputation for being powerful and knowledgeable in the series, and her catch phrase is "I know everything". She is the younger sister of Gaen Tooe and aunt of Kanbaru Suruga.
Appearance-wise, she has long Brown Hair that typically covers one of her Brown Eyes. Her typical attire is hip-hop inspired, consisting of a green and white Baseball Cap as a Hat (often worn sideways), a green off-shoulder t-Shirt, Red Pants, and dark red Flats for Shoes. For accessories, she usually wears red Prayer Beads, a yellow star-shaped Pendant Necklace, black Wristbands, orange and yellow Headphones (usually around her neck), and carries multiple Smartphones.