Reiyūkai, or Reiyūkai Shakaden, is a Japanese Buddhist new religious movement founded in 1919 by Kakutarō Kubo (1892-1944) and Kimi Kotani (1901-1971). It is a lay organization (there are no priests) inspired by Nichiren Buddhism, but not affiliated to any particular sect.
Reiyūkai considers itself the grandfather of lay-based new religions devoted to the Lotus Sutra and ancestor veneration. Reiyūkai membership currently stands at 5.14 million members, with the majority living in Japan. Provided by Wikipedia
The philosophical foundation of the lay Buddhist practice of the Reiyukai, as depicted in the Lotus Sūtra / published by the Reiyukai