And How much risk does it have on their career and reputation?
This is the only part of your post I feel like I can comment on, but it's in the form of a question – why the worry about taking an alias? The fact that you're concerned at all tells that you have anxiety with using your real name.
Here's a fact -- eventually, even an alias may be linked back to you when you enter the realm of more "respectable" wor, but ... at that point, it means you have enough interest around the work you really want to be doing that it shouldn't matter so much. If you hadn't been a success, people wouldn't bother digging into your background so deeply.
Also, you're basing a lot of your fear on the kind of cultural thinking that's rapidly dying out, and will face eventual extinction. Especially in our evolving, accepting, liberal and sexually freed culture, I doubt that the fact you once drew dirty pictures will matter much in the year 2025 (unless you live in Syria or something).
If all you need is to make money somehow for now, but it bugs you to be firmly identified with it ... then go ahead and do it and pick a fake name. If you actually WANT to be making this kind of art, though, and it genuinely intrigues and inspires you, then it means you should cast off all other concerns and dive in wholeheartedly and to HELL with your "reputation." I promise you -- the Western world has changed a lot in 30 years, and is still changing rapidly. Nobody you want to be in your life will be judging you for it 10 years from now.
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