I'm not a lawyer either, but a quick search shows that state law is the thing this could be breaking. It's not criminally punishable to possess it, but acquiring or distributing it via the internet is potentially illegal. Here's a page from a Massachusetts lawyer discussing the legality. https://anthonyricciolaw.com/is-lolicon-legal-in-the-us/#:~:text=Under%20federal%20law%2C%20a%20simple,state%20laws%20regarding%20child%20pornography.

Edit: apparently that's only part of the requirements for illegality. The other part is sexuality or not having "value" which is subjective. Either way, it's a dice roll on criminal acts.