In Japan, the Eirin (Film Classification and Rating Committee) uses the "R-18+" designation strictly. For Maguma No Gotoku , this rating is not just about nudity (which is common in Japan’s R-15+). The suggests:

It's 2004 in Japan, and the streets of Tokyo are alive with the hum of neon lights and the whispers of the underworld. The Yakuza, Japan's infamous organized crime syndicates, have long been a fixture in the city's shadows. But in this story, we'll follow the tale of a former Yakuza enforcer, known only by his codename: "Maguma" (meaning "bear" in Japanese).

Maguma no Gotoku (マグマのごとく), also known as Magma no Gotoku or by its English title Humidity Love

Disclaimer: This film is rated 18+ for mature themes, violence, and disturbing imagery. Viewer discretion is advised.

"In 2004, Japan was abuzz with various cultural and technological advancements. The year marked significant releases in the gaming world, a sector that has notably contributed to Japan's pop culture globally. One of the notable mentions from that period is the evolving narrative of 'Like a Dragon' (Maguma No Gotoku), which in 2004 was on the cusp of making significant waves in the gaming community.