I noticed this issue today as well. after uninstalling the virtualcam, I was left with a phantom "OBS Virtual Camera" option that showed an OBS logo but did nothing else.
I searched through the registry for that exact string, and found the following:
Code:
Computer\HKEY_CLASSES_ROOT\CLSID\{860BB310-5D01-11d0-BD3B-00A0C911CE86}
Computer\HKEY_CLASSES_ROOT\CLSID\{A3FCE0F5-3493-419F-958A-ABA1250EC20B}
Computer\HKEY_CLASSES_ROOT\WOW6432Node\CLSID\{860BB310-5D01-11d0-BD3B-00A0C911CE86}
Computer\HKEY_CLASSES_ROOT\WOW6432Node\CLSID\{A3FCE0F5-3493-419F-958A-ABA1250EC20B}
I renamed each of them to see which would change, and the third one was the culprit, at least as far as appearing in the camera selections. Each of these was connected to something called "VFW Capture Class Manager" which I am unsure of. Initial google searches also mention a lot of malware, but that's really not my area of expertise, so whatever.
After removing these keys, the phantom camera was gone.