No, just that Studio Pierrot produces things that are not suitable for Christians. Urusei Yatsura contained nudity, for example, and a barely clad heroine, & risque dialogue.
Urusei Yatsura (or Ranma ½ or InuYasha, as they're also by Rumiko Takahashi - Ranma ½ actually having been one of my favorite series since high school) isn't porn, though, and neither does nudity, with or without ribald humor = porn. If it was porn, you'd see genitalia, masked over by mosaic censoring, since Japanese law mandates pornographic material be censored (although when licensed and released in the U.S. the censoring is removed - but that material is
not mainstream at all, clearly marked as 18+ and Adults Only, and sold in obscured packaging if a place like FYE carries it; otherwise you'd have to go
actively looking for it). 'Genitalia' in this case is specifically the crotch area in graphic detail, not breasts.
It's just like in American cinema - you can't put National Lampoon, American Pie, or serious drama/romance fare that simply contains nudity in the same category as Debbie Does Dallas, Girls Gone Wild videos, all manner of stuff put out by Playboy, Hustler, Penthouse, or all the hardcore pornography that the Internet has available on it. The latter is porn, the former is not.
The Japenese culture doesn't worry about decency too much in the world of anime. The conventions should be boycotted by any Christian, and parents need to be careful what they let their kids watch. Keep in mind it's a slow sneaky development from innocent to porn in this garbage.
They don't adhere to Victorian ideals of decency (because they never did), but that doesn't mean they don't worry about it or have standards that producers are not allowed to cross. Over-the-air broadcast cannot show either graphic nudity (i.e. no female nipples or such; vague outlines of body shape may be ok, and when there is detail, the parts are usually blurred or have convenient visual gags covering them like fog or nosebleeds or bats or so on) or on violent programs, blood that's actually red, for example - on the air, it's recolored to black, although the DVDs are completely uncensored if those elements were not actually part of the scene to begin with (American companies like Viz and Funimation are the only ones who produce 'clean' DVDs for the series they've licensed, and then only for the ones that air on TV - Dragonball Z, Bleach, Naruto, etc.). Cable and satellite broadcast may or may not have those restrictions, similar to how cable companies in the U.S. don't have to report to the FCC - most standard cable channels like TBS, Comedy Central, Sci-Fi, and USA
voluntarily follow the FCC guidelines to some partial extent, but they don't have to. Premium channels like HBO and Showtime generally don't follow them at all. The situation in Japan is remarkably similar.
Japan is not scared of nudity, partly because the bath house culture is a very prominent fixture in the society (and bath houses
are usually gender-segregated, although young children of either sex will accompany their parents into the respective area of the bath house; mixed bathing is usually an element of honeymoon retreats or sometimes generally in the country, not the cities). It's simply American Puritanical attitudes that killed it here, save for the occasional communal shower at the gym/gym class - in Europe it's not necessarily as prevalent either but saunas and spas are common (mixed or not), as well as nude or topless beaches (granted, we have those in the U.S. also, but far fewer high-profile ones than you'd see in Europe or Australia or practically anywhere else on the planet). There's nothing antithetical to Christianity about nudity - heck, baptisms in the Early Church were performed nude, and there's plenty of Christian art from the Renaissance and Medieval period that contain nudity.
This is all ignoring the fact that most anime and manga is
not made for kids, and for 15+ and 17+ material, is aired at times of the day when children would not be watching = after the so-called 'watershed' hours, normally between 10 PM and 2 AM. The age range for most series/movies is 13 years old and over, with most of the ones that cater in sexualized fanservice/nudity/so on for either the 15+ or 17+ (still not porn = R-rated, not X-rated) demographics.
The bottom line here is, there is nothing in mainstream/broadcast anime that's more offensive, qualitatively, than shows we have here in America like The Simpsons, South Park, Family Guy, and American Dad - I would actually argue that the aforementioned American programs are
more qualitatively offensive than most mainstream anime. The only difference is that anime is not restricted to being satirical comedy series or Saturday morning kids' fare, and can cover the full breadth of genres that novels, Hollywood movies, and prime time live action series can cover - often with better plotlines than the standard prime time and Hollywood drivel, I might add. Just because it's animation doesn't mean that those elements are suddenly more offensive or tawdry, or that one should hold it to a different standard than live action offerings or American media. And in addition to that, not
all anime falls into that category to start with, or they only use it sparingly. Heavy fanservice series are still a minority when you consider the sheer amount of anime and manga produced yearly.
And having been to a couple of conventions, I'm wondering what con you're talking about - I've not seen anything approaching the sales of sex toys or pornography in the vendor's room. If the con does have an area for that you would likely have to be carded to be able to enter that specific area of the hall, and that is not a fault of conventions in general, just the one you attended. Cosplay costumes sometimes being on the level of swimwear and the like is not all that shocking, but it is by no means the average. At its worst, it's no worse than what you'd see at a beach (and I mean a regular beach, not a nude/topless beach).