Hmm, yes that's not exactly the most discreet charge to pop up in your history. It looks like with the payout mode I'm using, it must list the 'merchant-on-file' (aka the company/username) for transactions. I don't think I can provide a separate name for charges.
But a wonky workaround might be: send me a message when you plan on purchasing a game (you can message here or at groinpaingames@gmail.com) and I can temporarily change the username to GpG, which is what should appear on the card. I'll keep an eye out for a more permanent solution in the meanwhile.