Entertaining futuristic film-noir adventure, but not for kids.
In this game, the player takes on the role of a futuristic mercenary who can use magic or technology to fight various ne'er-do-wells.
It is absolutely not for the younger set.
Much like the film noir tales that inspired it, Shadowrun Returns is a complex game with a very grey system of morality. Players can opt to shoot their way through a problem or talk their way around it. References to drugs and sex are fairly common, but again, part of the milieu of the game - the protagonist is essentially a futuristic Sam Spade, hired to solve a grisly murder. To that end, the player encounters sex workers, drug addicts, and various other questionable characters, some of which are very thinly sketched, others are given motivation and explanation for their actions. There's blood and guts and carnage and some body-horror type content, but for a sufficiently mature player, the experience is overall extremely rewarding, with a thoughtful (if extremely linear) plot and challenging action sequences.
To that end, I wouldn't say there's "too much" sex/violence/swearing, because again, this is absolutely not a children's game. If you're interested in a game in the style and tradition of the Baldur's Gate series (or the first two Fallout games), then this is absolutely worth the money.
But I wouldn't give it to anyone under 15, for sure.