Common subjects which are considered Mature Content are nudity, excessive violence, excessive blood and gore, sexual themes, strong language, or ideologically sensitive themes.
The Entertainment Software Rating Board (ESRB) is an American self-regulatory organization that assigns age and content ratings to consumer video games. ... The ratings are designed towards parents so they can make informed decisions about purchasing games for their children.
Mature 17+ Content is generally suitable for ages 17 and up. May contain intense violence, blood and gore, sexual content and/or strong language. Adults Only 18+ Content suitable only for adults ages 18 and up.
Titles rated T (Teen) have content that is generally suitable for ages 13 and up. May contain violence, suggestive themes, crude humor, minimal blood, simulated gambling, and/or infrequent use of strong language. ... May contain intense violence, blood and gore, sexual content and/or strong language
https://www.esrb.org/ratings-guide/
