Typically, Naruto in a 'gangsta naruto fanfic' is a tough and street - wise character. He's not the naive kid we see in the original. He has a bit of an edge, using his natural exuberance and ninja skills to navigate the rough world he's in. Sasuke might be a brooding, more mysterious figure, perhaps with his own hidden motives within the 'gangsta' setting.
Well, the Gangsta manga ends with a mix of closure and ambiguity. Some characters get the resolutions they deserve, but there are still elements that make you think and wonder about the future.
It could mean that there is a fan - created story (fanfic) about Naruto where the characters are depicted in a 'gangsta' - like style. For example, they might have the attitude, appearance, or behavior associated with gangsters in a modern or unique setting within the Naruto universe.
Probably not as popular as the more traditional Naruto fanfics. The Naruto series has a large following for its original ninja - based story, and the 'gangsta' theme might be a bit too far - fetched for some fans.