Is Makai Toshi Shinjuku hentai?
English title: Demon City Shinjuku
No
Rated R (17+ (violence & profanity)) on MyAnimeList and not tagged as Hentai.

OVA · 1988 · 1 episodes · R - 17+ (violence & profanity)
Adventure, Gore, Horror, Romance, Supernatural
On the rooftops of Shinjuku, Genichirou Izayoi fought against Levih Rah, a man who sold his soul to obtain demonic powers, and lost. Ten years later, Shinjuku remains a wasteland of demonic energy while the rest of Tokyo remains largely untouched. One day, Genichirou's son, Kyouya, is watching the news when he sees that Japan's beloved prime minister has been attacked by demonic forces. While he lacks confidence in the Nempo powers he inherited from his father, Kyouya is the only one who stands between Levih Rah and the rest of the world. Along with the prime minister's daughter, Sayaka Rama, Kyouya journeys into Shinjuku to see if he can accomplish what his father could not. [Written by MAL Rewrite]
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