General Discussion

@Bigheart711: Yeah, but in her case that is the joke.

@Sonata said:

Cant forget the ladies of Queens Blade

Uhhh I dont think I have to explain this one O_O

......yeah I agree.

From everyday's fanservice to hentai there is no line separating black and white, but a full scale of grey, where we find ecchi and the boundaries are very blurry. (If you want a short answer, go to the last line of this message.)

At least from my point of view. For instance it's weird that in some places:

1. Men and women have nipples.
2. Men don't have breasts, women have breasts.
3. Men can show their chest and their nipples.
4. Women can show their breasts but not their nipples.
5. The characteristics part of the sexual dimorphism are not a problem for censorship, but shared characteristics are, for only one gender!

I really can't see the logic in that. Topless is socially accepted in many places today, it was the cultural norm in the ancient Egypt. Full nudity in some (nudist) places in "modern civilization" and it's culturally the norm in some tribes in the Amazon. The cultural norm in some places is the veil for women, and in other places the burka. Internet is global, wikipedia is uncensored and genitalia are pictured, but no explicit sexual images, which are the most "problematic", however explicit sex between animals is not a problem in most contexts. (Warning: generalization ahead) "Japanese culture" is considered as "pervert" by "american culture", however genitalia must be censored even in porn, it's mandatory according to Japanese law (not the case in America). The United States praise their "freedom", but when they think about nudist beaches they think about Europe. Including a little nudity will take the age rating for some media up subjectively (IMHO) faster than violence (or gore or terror), headshooting half-rotten zombies is culturally (in some cultures) way more accepted than fighting games where women show "too much" skin.

Sex was a taboo before because it was associated with reproduction. Now science has provided us with (new and better) contraceptive methods, but the culture is lacking behind and sex is still a taboo. The problem is: the lack of knowledge about sex, about contraceptive methods and all this general context is to some extent preventing people from practicing more sex (as traditionally) which could be considered good for some people (for reasons I don't really know), but to a greater extent, in the current context, it's doing something that is clearly bad, it's preventing people from having a sexual education that would allow them to prevent undesired pregnancies and sexual transmission diseases. Nudity and the human body are also taboos, the perception of the human body is distorted and this causes problems that lead to painful plastic surgery in some cases, among many other problems due to self-rejection, complexes, etc. There would be much less "perverted" people if the normal and natural sexual appeal was accepted as something normal and natural. We could also speak about the differences between chimpanzees and bonobos and many other things, but if you got reading so far I think I will just thank you and finish this. So I think there are good reasons to think that:

1. Much of what is being done is some form of culture preservation, for an arbitrary set of cultures, while there is no objective or rational reason to consider these cultures more valuable, better or more worthy of this "preservation". There is no reason (a priori) for it.
2. The implications of much of what is being done are negative and harmful. There are motives (a posteriori) not to do it.

Well, to sum up, I have no clue about what is PG-13 and why is it so. But you may be interested in this list:

http://www.animevice.com/profile/trylks/boderline-anime/121-2957/

PD: Naruko (Naruto's sexy no jutsu), I guess Naruto is rated PG-13. At the same time, the sexy no jutsu is meant to be hentai, in some way, it's meant to be used as some form of distraction by nudity and sexual appeal, so it can be considered as hentai in "Naruto's Universe", and then veiled and "conveniently censored" for consumption in "our universe". I could not find an image, so here you have a video:

@EganTheVile1: I don't really understand how censorship works.

She is dressed: http://www.animevice.com/saiki-misaki/18-29746/all-images/84-213119/misaki_2_/83-308920/

She is not: http://www.giantbomb.com/princess-ruto/94-2561/all-images/52-294528/ruto2/51-671423/

There are many characters in the Looney Toons that don't wear any clothes, you may say they are not human, but... is Felicia human?

All I see is that it doesn't matter which are the limits of censorship, there is no way to set them clear, and even after good attempts there are characters jumping in and out of them constantly.