Just bought this and I might be absolutely dumb on how to set it up since I wanna make this a VRChat model and I don't know crap about Blender at all :/
Viewing post in FoxiPaws' Azalea Latex outfit & Hoods comments
You basically mix the things with the original avatar.
I posted a pretty lengthy tutorial in the comment section of this product: https://dein-ra.itch.io/jwmasccaninelatexoutfit which is also a latex outfit, but for a different avatar.