Ah, you’re not alone. Most people have those worries, especially early on. I wouldn’t sweat it too much though, for a few reasons:
- IANAL, but I believe in most places Copyright is automatically assigned to the creator of a work. Making and posting a character, provided it doesn’t already exist, is enough to make it legally yours… so as long as you don’t have people taking your designs directly off of your hard-drive there should be proof that you own your work.
- With that said, while IP theft does happen and reports/DMCA can be used to deal with them…it’s not usually something that will hurt you much in the long run and it’s not worth the time to actively hunt down unless you’re a big business that can spare the effort. Personally, what I do is deal with anything I run into (usually starting with a quick message) but otherwise don’t spend time looking for folks who infringe. Most people copying work don’t mean badly, they just don’t know better.
In other words, your worries are totally natural but I’d reassure you that it shouldn’t be a major issue.