Nisemonogatari" is a sequel to "Bakemonogatari", a coming-of-age novel about a boy and a girl who are involved with "monsters" that appear around Naoetsu High School in the early 21st century. The first volume is about the main character, Koyomi Araragi's older sister Karen, and is the sixth story "Karen Bee", while the second volume is about her younger sister Tsukihi, and is the final story "Tsukihi Phoenix".