In short
- Article 175 punishes distributing or publicly displaying obscene drawings or data in Japan: up to 2 years' imprisonment or a fine of up to 2.5 million yen.
- The law never defines "obscene". Courts still use a 1957 Supreme Court test from the Lady Chatterley case.
- Mosaics, black bars and whiteout are how the industry regulates itself to avoid charges.
- Police still act: in 2026 an Article 175 inquiry made Fantia rewrite its rules.
- FAKKU and Irodori Comics sell uncensored English editions outside Japan.
What Article 175 says
The current text of the article, on Japan's official e-Gov law database, punishes anyone who distributes or publicly displays obscene documents, drawings, recording media or other objects, or distributes obscene electronic records by telecommunication. The penalty is up to two years' imprisonment, a fine of up to 2.5 million yen, a petty fine, or both prison and a fine. A second paragraph covers possessing or storing such material for paid distribution.
Why hentai is censored with mosaics
The code does not say what "obscene" means. Courts rely on the Supreme Court's 1957 Lady Chatterley ruling, which, as summarized by the Comic Book Legal Defense Fund, calls a work obscene if it excites and stimulates sexual desire
, is harmful to the normal feeling of shame
and runs counter to good moral concepts regarding sex
. Nobody can say in advance exactly where that line falls, so publishers obscure exposed genitals and let the industry police itself.
The law is used against comics. Publisher Motonori Kishi was convicted in 2004 over the manga Misshitsu (Honey Room), and the Tokyo High Court upheld the conviction while changing the sentence to a 1.5 million yen fine. In 2013, Core Magazine suspended the 18+ magazine Comic Mega Store after a police investigation under Article 175.
What mosaic rules look like on platforms
Japanese platforms write the rule down to the pixel. pixiv requires mosaic squares of at least 4x4 pixels, and 1/100 of the image's length once an image is longer than 400 pixels, on the same layer so software cannot undo it. pixivFANBOX and Ci-en use the same formula. Fantia asks for thick black or white bars or a mosaic, and the parts must stay unrecognizable even shrunk to thumbnail size. Skeb rejects delivered files whose censor layer can be separated.
WEBTOON goes the other way: it bans nudity outright, so box and mosaic censoring are banned too, and any covering has to be part of the drawing.
Fantia's 2026 rule change
Fantia tightened its mosaic rules retroactively on May 25, 2026, pulled the change back for 2D work four days later, and said on June 25 that a police inquiry under Article 175 about live-action content had caused it. The full timeline is in our story on Fantia's mosaic rules.
Uncensored English editions
English licensors state their editions plainly. FAKKU's subscription page offers completely uncensored English hentai comics. No black bars and no mosaics.
, although its tag index also has Mosaics and Whiteout tags for books that keep them. Irodori Comics sells uncensored English doujinshi and blocks users in Japan from viewing or buying uncensored content, citing governmental regulations in Japan
. We found no legal source that explains the cross-border position beyond Article 175 itself, so we report what the licensors say.
Stores that sell uncensored work are compared on uncensored hentai sites. For the terms, see hentai and doujinshi; for what creators may post, content rules for creators. The full term list is in the glossary.
FAQ
Is uncensored hentai illegal in Japan?
Distributing obscene drawings in Japan is a crime under Article 175, and Japanese publishers and platforms treat uncensored genitals as falling inside it. That is why pixiv, FANBOX and Fantia require mosaics and why Irodori Comics blocks users in Japan from its uncensored editions.
Why do some English releases still have mosaics?
Some books keep the censorship of the Japanese original. FAKKU tags those titles Mosaics or Whiteout, so readers can filter them out.
Do western porn comics have mosaics?
Generally not. Article 175 applies to distribution in Japan, and western studios such as Affect3D and Kirtu publish no mosaic policy.