The specific file or "piece" you are looking for, Girlvania: Summer Lust Expansion Pack (Legs & Feet Version 1.2.2 Portable), appears to be a community-made mod or expansion for the 2016 title Girlvania: Summer Lust.
Updated Physics: The expansion includes minor tweaks to movement physics, making the character feel slightly more agile to match the "summer" theme. The Advantage of the "Portable" Build The specific file or "piece" you are looking
Conclusion
(often associated with version updates like 1.2.2) introduces specialized animations and interactions focused on lower-body aesthetics. Overview of Girlvania: Summer Lust Excellent, unique visual style