Keep in mind that this is not an official review. It's more of an overview of the content issues in Furuba. Keep that in mind. ^_____^
Sex/Nudity: When the Sohmas are hugged, they turn into animals. Likewise, when they un-transform, they aren't wearing any clothes (They either got ripped because their animal form was too big or they slipped off because their animal form was too small. Luckily Takaya-sensei has spared us alot of embarrassment by placing a convenient cloud around most un-transformations. Unfortunately, this cloud is the general censor device, but is not an across the board protective measure. There are a few instances where females tranform back. One instance when a little girl transforms back and we see most of her body but it is SUPER undetailed (there's not even a belly button of this chick). Another instance in the first volume, Kagura un-transforms and, while mostly eclipsed by another character and her arm strategically placed, we still see a good portion of her hip and a little of her chest (But I don't think we see anything that transcends clevage.) Additionally, When Kisa, a ten year old, untransforms, we see quite a bit of her. The largest exception to the cloud rule that I can think of is around volume 11 when Rin Sohma transforms and we see an unobscured shot of her undetailed breasts. This nudity is more "babie-doll" style, but I'm still not sure that I'd be comfortable loaning it to a guy. (Oh, wait, yes I would. I drew a lovely one piece bathing suit on MY Rin.
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The next and most objectionable issue upto volume 15, is that fact that in 14 we see a very clear reference to to the fact that [spoiler=the character's names]Rin and Haru[/spoiler] had sex. All we see is the two of them under covers. The female character involved is not wearing a shirt, and we see her back and a little bit of her breast. Additionally, this same female character tells an older member of the Sohma family that if he can tell her some information she desperately needs, she will give herself to him (give yourself=sex. Naughty girl.)
Lastly on the sexuality score: in the first few volumes, there are MANY jokes that reference homosexuality. This manifests its self primarily in the actions of a couple characters who act[/or
possible are] gay. While I think it's quite obvious by the latest volumes that the characters in question aren't gay, they still say really obvious dumb stuff to weird people out. (And it works, too). In general, these kinds of jokes consist of Shigure and Aaya exchange some sort of homosexual innuendo, and then they turn into these starry eyed chibis and say in a dumb font "ALLLLL RIGHT!!!" Honestly, it's played for laughs, and at one point a character who is a long time friend of the two in question says "You never got tired of that, did you?" And in my opinion, he means, "Y'all never got tired of those dumb jokes, did you?"
One of the larger homosexual references in the domestically released 15 volumes occurs in volume three-- I think-- when Aaya, who is pretty much a pervie, tell one story that seems to have homosexual undertones, but his object in making the questionable statement was to draw attention away from some friends who had gotten into deep trouble. It worked. Whether has was serious about what he said or not, the world may never know. A lot of the information that could be interpretted as "homosexual" simply comes from the fact that the many of the men in the Sohma family are very close. There are several instances when characters say things like "he was my first love," but having read 15 volumes, I'm confident they mean these statements as extremely strong statements of friendship.
Language: Well, there's a quite a bit of language in Fruits Basket. First, Kyo is a major hot-head, and his mouth reflects that. Hatsuharu has a bit of a split personality, and when his "dark side" is showing, he can espouse some pretty colorful language. When Yuki is properly insulted, he can let a word slip too, but the first two are the main potty-mouth characters. As far as what is said, the profanities are more minor, IMHO. Things like: D*MN, B*STARD, H*LL, are the words said the majority of the time. There are never any "F" bombs of anything.
Violence: A little blood. Some of the characters like to kick eachother around and they get blood lips every once and a while, but no flying body parts. In later volumes, Akito gets pretty violent and we see some bad cuts and bruises. The bloodiest I acn recall things getting is when Akito hurt [spoiler=character]Hatori's[/spoiler] eye.
Bad Religion: Well, there is talk of the Zodiac, but it's never used to predict fortunes or anything. It's more a backdrop for the story, rather than an active player in the plot. Honestly, most of the Zodiac talk is centered around a banquet where God invited all the animals. If you think there's somethign blasphemous about that, feel free to be offended.
The largest element which might lend itself to causing religious offense is the revelation that [spoiler]Akito is the God figure in the zodiac story, and says to Tohru that he is the Zodiac member's god. To me, what this meants was simply that he has the power over them.[/spoiler]
The religious element in Furuba has never really bothered me. Basically, I'd say that if you can handle the religious element in, say, Hercules, you shouldn't be bothered by Furuba.
I hope that helped. Honestly, Furuba is one of the cleanest manga I've ever read. It has thus far avoided gratuitous nudity, and the scarce sexual references that have been made are quite tame when compared to popular movies or other manga. Additionally, the values of unconditional love and the redeeming power of forgivenes that are taught in Furuba have made it well worth reading to me. If you're atleast 14 or 15 and you are confident that the issues mentioned above wouldn't be a stumbling block, I'd recommend this title to you.
There's really nothing more that I can think of. Sorry for the length of the post, but when I do something, I try to be thorough. Hope it helped.