Copyright and Hentai and cosplaying?

So humor me on this.

When in the USA. How does copyright work with hentai material?
To say a situation....

What if someone made a product featuring a cosplayer. Is it copyright infringement if the
model didnt give you permission? But at the same time, who gave them permission to use the
character to cosplay and make prints off of? ( they didnt ).

But when it comes to Hentai material. Books, Characters and so on. Being in the USA how does it
go making material with those characters being that they all based outside the country? I see T-shirts
and so on.

Im wanting to make some products based off the franchises. ( Maybe partner with Fakku if they ever reply to my email ).
But if I could I could just do it on my own. Im just unsure how all this works when I see sooooooo many cosplay chicks
obviously breaking copyright and nothing is really done about it.

As a photographer the first one depends if it in a public place aka on the streets or in a con. If they're the only one in the photo yes you need their permission to shoot and a model release if you want to use that image in any ways that profits you or a company. If it a public event which you don't need an entry fee or permission then that a grey area so you still get the release anyways for liability reasons. Journalistic reason you don't because a public need and press.

As for copyrighted material like doujin i don't believe as long as you just don't steal that copyright like you own that character. You're cover by parody laws which is nearly the same as japan just more known. So if you want to shoot a porn with a cosplayer in character You need a model release and a contract since you have to pay them and keep records they're over 18. If you just want to do non porn you don't need the age records since they're no sex or nudity.Doujins and merch It all depends on the work and the money. Nintendo will sue you.

Im not planning to use photographs of these people. Its more about the "Character" they are using. Say if I made a figure,drawing and so on of the model IN cosplay. How can they use the character, but no one else can use their "persona" while they are in Persona anyways?

But mainly I was wanting to do Hentai character MERCH. No models or anything. But create little trinkets based off the Doujin.

I mean, people make merch of characters all the time. If you go to an artists' alley at a convention, it's pretty much all drawings and pins and keychains of characters from anime and video games. Hell, some people even make dakimakuras.

I think it comes down to each work individually. Like, people making that merch probably isn't fully legal, but Nintendo and Shonen Jump, etc. aren't going to bother going after them because they're small fries. However things like fan games that get popular might get shut down because they're on the internet and have a lot of reach. Similarly, if someone made some merch that got super popular of say, Persona 5, Sega/Atlus might jump on that, idk. Probably would have to get a lot of attention though.

However, if you made some merch of like, an indie web comic without their permission, the creator would probably get pretty pissed. Unless it was copyrighted, idk if they could do anything (I'm not sure how it would work), but it would still be kind of douchey.

My plan was to make some products based off hentai comics. Not claiming it or anything. Will have their names and such on it. I work making products so I have the skills to make some professional looking stuff. Kinda like a celebration of the genre.

Biggest issue is that many of the artist are very hard to reach. Many names arent contactable names. And with all the over seas vs USA it's kinda hard to figure it all out. Like you said. The merch is everywhere.

It's just weird. I spend all day making poorly made ripoffs from people who dont even put in the effort to respect the art. I know I could do better. And would love to actual work with the artist. Maybe they will reach out for me to do so once I start doing it.