Bilibilibangumimedia is handled by the media route, which reads the site's own rendition list before choosing anything. No credentials are involved anywhere in this path — neither yours nor ours.
Two ways in: the box above, or prefix the Bilibilibangumimedia URL you are already looking at with tikt.com/:
tikt.com/https://www.example.com/path/to/media
Three steps, start to finish
1. Copy the Bilibilibangumimedia link
Use the address bar or the platform's own share button — both give a URL the extractor recognises. Point it at the single item you want, not the page around it.
2. Let it read the renditions
Paste the URL above. The extractor asks Bilibilibangumimedia which renditions exist for that item and picks the best progressive one rather than assuming a quality.
3. Save what comes back
The file arrives in the container Bilibilibangumimedia served it in, and the extractor does not rebuild it — so what you end up with is what the uploader encoded, for better or worse.