Nudixa review
Nudixa offers text-to-image generation and lets you build on an image already in your account. The public policy explains what happens when you choose to bring in a source image.
What happens to a reference image
Nudixa says it re-encodes uploads to remove embedded metadata, checks the content, then stores the processed image and a thumbnail in the account. The terms require the necessary rights and the consent of any adult depicted. The public generator describes a single free image without a reference, subject to availability, and charges credits for batches.
An account asset or a temporary cache
NovelAI documents a temporary encrypted cache for uploaded images that can last up to one hour. Nudixa’s policy describes storing the processed reference and thumbnail with the account. That makes a difference if you want to reuse your own fictional artwork across sessions or prefer a shorter documented storage window.
Anabel’s take
I'd start with text alone for a first character design. I'd save an original fictional reference in the account only when I intended to use it again across several images.