 As a production company, Mukai's films were distributed by other studios, including Nikkatsu, which used these films to supplement their "Roman porno" series triple-bills.During the 1980s, when rape-themed films were popular, Mukai produced some of Nikkatsu's most extreme examples of the genre, including the "Subway Serial Rape" series (1985–1988).Mukai produced celebrated "Roman porno" director Tatsumi Kumashiro's final film, (1995).