Likely a custom character name or a specific version of a model ("Judy Version V").
Ugoira animations and metadata · Issue #69 · Nandaka/PixivUtil2 Rescraft_JudyV_anim.zip
These are binary or ASCII files that define how a character's skeleton (rig) moves over time. In engines like Unity or for specialized J2ME clones, these files store keyframes, rotational joint data, and transition parameters. Likely a custom character name or a specific