(One of my most favorite furry artist around the web.)
KD钙 (KD_gai)'s mostly complete collection, this includes the artist's Pixiv, Itaku, and Twitter posts, several online image galleries, and other people's account (commission), I deduplicated them manually, removed some SFW ones, renamed and sorted in time order (oldest-newest).
The latest Real-ESRGAN image restoration model was used to upscale (4.0x, as the training model was designed for) and restore (denoise, remove JPEG artifacts) the image.
Some of the output file's resolution has to be limited to 6K level using Lanczos (2-lobe) resampling, this results in 2.0x~4.0x effective scaling.
The Real-ESRGAN took about 5 hours to crunch down all 200 images on my machine.
All uploaded pics were compressed with lossless PNG format, in compression level 9.