All payments and credit cards are handled and stored via Stripe a third party payment processor who’s security is arguably more impenetrable than that of major banks. Here is their published security info: https://stripe.com/help/security
From a credit card number storing perspective, there is no way for any employee at Comic Cartel or Stripe to access them, not even the developers.
No way josé. All credit info is stored securely on Stripe’s ridiculously secure servers. Go here to read about how secure they are if you want: https://stripe.com/help/security