I always wonder, would Akira Yasuda approve of the hentai drawn of Morrigan and Felicia?
Would Yuji Uekawa be fine with how Amy and Rogue the Bat are drawn on FA?
Is Lauren Faust upset that not every My Little Pony picture gives her credit?

No, don't be stupid. It's fanart.

And as long as no one is making a profit off of another person's work, nobody should stop you from drawing or having drawn characters you personally enjoy for whatever reason.

Long before I started posting on FurAffinity, I hung around a forum, a forum in which a group of people shared ideas and came up with the Kaiju Girls. Anthropomorphic females based on popular and not so popular TOHO kingdom monsters. I loved that forum, it was so fun, even to the point where I just had to commision pictures of these girsl to post on the forums to share. Sure the content may have no been for everyone. We can all admit stuff like hypnotism and masking can seem weird to others. But I would always post artwork of a much safer content. It was good times, but like good times. They always end.

Eventually more people came..and with them more kaiju girls. some based on monster from other properties, others based on monsters that we already had. The web site and forum owner tried his best to contain it all. Limiting and at least claiming some bit of ownership over each Kaiju Girl made.

But selfishness and hypocrisy is one thing that can never be contained on the internet. Even from the owner.

Eventually it became who could draw who, who was in a relationship with who, who owned who, who could wear this or that, and lord helped you if you even so tried to do fan-art of a Kaiju Girl. Eventually it was just too much and too maddening and the owner washed his hands of it. erasing the Kaiju girls from his site and leaving everyone to fight amongst themselves. but he isn't without blame. Very much so.
One thing I pointed out was making money of the characters. He did and for that he brought a lot of it on himself.
Now I don't remove blame from myself, I can claim that I have made mistakes in the past with them. Mistakes that are still brought up, but I do my best. and one thing is I never claim to own any kaiju girl. Though I have had a tiny hand in making two of them. :P

I still believe that the Kaiju Girls can be what they once were, a fully realized community, that everyone shares in. Artists like Coug'r have shown me that selflessness can happen.

As for the "creators" of the girls based on someone else's property, I'm trying to walk a line here, between your needs and common sense. I will gladly give credit a Kaiju Girls creator, but I will not censor my or anyone's artwork depicting them.

Because it's fanart.