Nisio IsinNisio Isin.

Nisio Isin (Japanese: 西尾 維新, Hepburn: Nishio Ishin; born 1981), often stylized as NISIOISIN to emphasize the palindrome, is a pseudonymous Japanese novelist, manga author, and screenplay writer. Nisio debuted in 2002 with the novel The Beheading Cycle (the first in his Zaregoto series), which earned him the 23rd Mephisto Prize at twenty years of age. In 2005, he began his long-running Monogatari novel series, which was published in 31 volumes as of 2026, and was later adapted as a highly-successful animated series of the same name, produced by Shaft.