Ryukishi was originally born in Chiba Prefecture. As an adult he worked as a civil servant until he was 30. During his time as a civil servant, Ryukishi developed a hobby in doujin circles and was part of a group to produce a work called Flowers, but it never released since the circle disbanded. Ryukishi later formed his own doujin group called 07th Expansion with his two younger brothers and created cards for the card game Leaf Fight.
Inspired by the visual novel Tsukihime created by TYPE-MOON, Ryukishi and his brothers decided to make their own novel game. Ryukishi had previously written various stage play scripts and took one called Hinamizawa Bus Stop and reworked it into Higurashi no Naku Koro ni. Higurashi has since become a pop culture phenomenon, and 07th Expansion's members grew as Ryukishi became involved in many more visual novel works.
"Ryukishi07" is a pen name, inspired by the character Reina of Final Fantasy V: "07" in Japanese can be pronounced as "reinana", and "Ryukishi" means "dragon knight", referring to the dragoon job in Final Fantasy. The character Rena Ryuugu, primarily associated with Higurashi, was originally a heavily-modified fan-rendition of Reina as well. The uniform worn by Reina, a highly modified rendition of the dragoon outfit, would also become the Angel Mort costume worn in-universe by Higurashi characters before becoming emblematic of 07th Expansion as a circle.
More recent works produced by Ryukishi have seen the presence of the wanya, a blob-like creature that seems to be his author avatar.
Many of 07th Expansion's works involve Ryukishi as both scenario/story writer and artist. Most character sprites are drawn and colored by him. For Rose Guns Days and TRianThology, Ryukishi drew a portion of the character sprites and had guest artists for other characters. Further in the case of TRianThology, Ryukishi wrote one story for it.
- Higurashi no Naku Koro ni
- Umineko no Naku Koro ni
- Higanbana no Saku Yoru ni
- Rose Guns Days
- TRianThology ~Sanmenkyou no Kuni no Alice~
- Ciconia no Naku Koro ni
Ryukishi has been involved in many other works as a writer.
- Kaidan to Odorou, Soshite Anata wa Kaidan de Odoru
- Verokia Dragoon Story
- Bakemonotachi ga Usobuku Koro ni ~ Bakemonohime no Kateikyoushi ~
Other Visual Novels
- Ryukishi07/O7th Expansion's official Twitter account
- Ryukishi's production diary from the official 07th Expansion website (no longer updated)
- Ryukishi07 makes a cameo appearance in the 2008 live action Higurashi movie. He can be seen in the crowd during the Watanagashi Festival.
- Higurashi no Naku Koro ni Famous Scene Investigation File 100
- Ryukishi07 Interviews (Epitanime 2012)
- The Untold History of Japanese Game Developers
- Higurashi Booster Book Interview
- Alone in the Dark: An Interview With the Creators of Higurashi When They Cry
- Illustration of Reina from the Higurashi no Naku Koro ni Official Character Guide
- Famitsu Special Interview 10/24/2019