Ichijinsha (一迅社) is a Japanese publishing company. They have published many booklets and manga series related to Ryukishi07's works.
Booklet Publications[]
- Higurashi no Naku Koro ni Special Edition: Hinamizawa Village Serial Mysterious Death Case Private Investigation File (Provisional)
- Higurashi no Naku Koro ni Official Character Guide
Manga Publications[]
- Higurashi no Naku Koro ni Comic Anthology
- Higurashi no Naku Koro ni Novel Anthology
- Higurashi no Naku Koro ni Shin Kitanshuu
- Higurashi no Naku Koro ni Kitan Senshuu
- Higurashi no Naku Koro ni Writer's Choice Series
- Higurashi no Naku Koi ni: All You Need is Love
- Umineko Biyori: Welcome to Rokkenjima!
- Umineko no Naku Koro ni Episode Collection
- Umineko no Naku Party ni