Parallel Space is a launcher. It is worth being clear about its reach, because it starts other programs on your behalf:

• It runs as you. No elevation, no service, no driver. The manifest requests asInvoker.
• It starts programs you configure, with arguments you can see and edit, and puts each launch in a Windows job object so it can report status and close that copy's process tree — and nothing outside it. The one exception is a Discord channel space, which is closed by process image name and therefore ends every running copy of that channel, including one started outside Parallel Space.
• It redirects environment variables (USERPROFILE, APPDATA, LOCALAPPDATA, TEMP) for spaces set to "isolated profile", so the copy reads and writes inside %APPDATA%\ParallelSpace\Spaces\<id>.
• It reads Start Menu shortcuts to list detected apps. This is read-only: it resolves .lnk targets and never launches anything while scanning.
• It does not patch, inject into, or modify any other application, and it makes no network requests. The only outbound action is opening a vendor's official download page in your browser when you click "Get it".

Your data stays in %APPDATA%\ParallelSpace. Nothing is sent anywhere.

Please open a security advisory rather than a public issue, and include the version and steps to reproduce.

Running several copies of an app is a normal thing to do with your own accounts. Some services restrict multiple accounts in their terms — that is between you and them; this tool takes no position and does nothing to hide or falsify anything.