Petitioned to rename with AI Generated because, well, it obviously looks like AI, but there were enough strange things to make me confident about that. They're also a bit inhuman with the amount of render variations they post on patreon.
Owner doesn't disclose it properly on his Patron or Pixiv profile, but most of his posts on Pixiv are tagged with AI and his Fanbox (now dead because the platform doesn't accept AI anymore) clearly states "Beginner AI prompter." So there's no room for doubt.