PlayStation game Omega Labyrinth Z has been banned from sale in the UK because it "promotes the sexualisation of children".
The Video Standards Council said the "likely harm" it would do to the young people it was aimed at meant it would not get an age rating.
Without a rating it is illegal to sell the game in the UK.
In a tweet, distributor PQube said its appeal against the decision had been rejected.
"This is a really rare occurrence, with only four games in the past 20-plus years having been refused ratings before to my knowledge," commented Ian Morris, editor of the Everybody Plays video game news site.
The game has also been refused a rating in Australia and Germany. PQube said it would also not be available in New Zealand and Ireland.
In the US it is expected to get a "mature" rating, which means it can only be sold to those aged 17 and older.
The ban is likely to mean that the title will not be listed on Sony's online store for the PS4 and Vita. UK sellers of the physical game are listing it as unavailable.
Set in a girls' school, Omega Labyrinth Z involves putting its female characters through a series of challenges as they search for a holy artefact in caves under the academy.
Many of these challenges and mini-games had sexual themes, said the VSC, involving players "touching" and "arousing" the characters and removing their clothes.
The characters are described as "young girls" and their voices and appearance reinforce this impression, said the VSC. One, referred to as a "first year", is depicted holding a teddy bear.
In its strongly worded statement explaining its decision, the VSC said the overall themes and content would be "unacceptable to the majority of UK consumers" and could cause significant harm to the "moral development of younger people".
Distributor PQube has yet to respond to a request for comment on the VSC's decision.
The game is the first to be banned in the UK since 2008 when the VSC refused to give a rating for the controversial shooter Manhunt 2.