Catherine is the upcoming PS3 and Xbox 360 game from Japanese developer Atlus. It is a spin-off of the Persona series of role-playing games. An adult one.
As evident by the game's launch trailer and now the promotional poster, Atlus wasn't kidding when it said it was making a game for adult players.
It is rated CERO C, which is ages 15-years-old-and-up. So expect more "suggestive" than, say, "explicit".
Catherine will be released this year in Japan.