Naoko Hayashiba (?? ??, Hayashiba Naoko, born on January 24, 1968), who is also known by the pen name Masaru Katori (??? ???, Katori Masaru), is a Japanese writer and manga author from Fukuoka.
She had a successful career as professional shogi player but quit during a sex scandal with another professional player, Makoto Nakahara, in 1995.
Since then, she has focused on writing and TV work.
She has written two novel series, Tondemo Police and Kiss Dakeja Iya, and the manga Shion no O.
In 2010, after a 15-year absence, she returned to shogi.