>>2772966Well, your model happens to have permanently recessed eye whites too.
It makes minimal difference whether it's hotpants or nipples (in the options that you have), and yes, that's what you will need to do if you want a correct metallic chain. A unidirectional physics chain will not work in this case unless you feel like unrealistically stretching the metal by adding some lower body weight to a link mesh.
You can take a look at the following models. While all of their implementations are the "unless" ones, you already know how to make an end of a chain link without deformation. The physics at the ends of the chain must not be able to move (slide), and their rotation pivots must be in correct positions, at the point of link contact. (You might want to reduce the diameter of the frontal connection ring and fix the clipping from bending the gobbo over, as it's easier than moving the whole chain.) The rotation of the ends must also be limited, you'll need to figure out the maximum allowed angles yourself.
コルセットピアスチェーン by azyazya — the simplest "unless" option where the whole chain is a single rigid with minimal weight and link deformation. It will not work on nipple piercing chains if their ends will have to be parented to different moving rigids, although with static breasts it will probably perform just fine. (But where's the fun in that?)
試作布 by WYKP for the FREYJA.sys motion. Has extremely detailed physics, meant to be attached to both hands throughout the dance. You will need to set external parent keys for the handles to be able to do it in MMM, however.
Collar with a leash that can be held by someone else. Distribution ended, so here's a reupload:
https://tstorage.info/edtxgqbx6vm7There's also a pic-related edit of it I made for the early version of my masochistic self-insert, but I'm not sure what's the difference besides shiny textures and IKs, looking at it now, years later. I doubt it's worth uploading.