[seiji]

Technically, no. If you are accepting credit cards from them, you can make their credit card statement line item say whatever you want and you can receive the money direct to your bank account (assuming Stripe usage).

If you receive the payments as an individual (as an American), you'll have them taxed at the normal federal income tax rate, state tax rate, and local tax rate, so you'll have to set aside 50% of your income for taxes.

If you're not sure how successful your venture will be, start off taking payments to yourself. If you grow bigger, then put a company behind it. It's annoying to form a corporation, maintain the paperwork on it, then end up only processing $50/month through it.