Karen is the sister of Koyomi and Tsukihi Araragi in the -Monogatari franchise.
Karen is a character from the Monogatari franchise and has made appearances in the light novel series written by Nishio Ishin, featuring illustrations by Vofan, and published by Kodansha. She has also made appearances in the anime series based off of these light novels: Bakemonogatari and Nisemonogatari, both of which are produced by Shaft and published by Aniplex . Her original design is credited to the writer and illustrator of the light novel series while her anime appearance is credited to Akio Watanabe. She makes her first appearance in Bakemonogatari #2.
Continuing her and Tsukihi's investigation on the charms infecting students that took place during the Bakemonogatari series, Karen eventually discovers that the culprit behind all of the acts is none other than Kaiki Deishu, a black market con-man dealing in occult items. Karen confronts him but falls victims to his ways and is infected by a Wreath Fire Bee charm and ends up bedridden. With the help of Tsubasa and Koyomi, she regains some of her strength and goes out to confront him yet again, but is stopped by Koyomi, who convinces her to let him take care of Kaiki.