New in the Japanese Journal of Analog Role-Playing Game Studies, an academic article offering “An Exploration of the Appeal of the Cosmic Horror Series of Gamebooks for Call of Cthulhu TRPG | RPG”. This considers, partly via online surveys, some of the reasons for the sustained popularity of the Call of Cthulhu RPGs in Japan.
The Call of Cthulhu series is said to be bigger than D&D in Japan, and synonymous with ‘tabletop RPG’. The success is apparently aided by the relatively simple rules, adaptability to different time-frames and sub-genres, and a strong player base among female fans (meaning male fans can ‘play with my waifu’).