Fringed Male Vest With Shirt from EP14 For FEMALE

Hey! It's because male frame body looks different than female one, it tries to adapt to female but as you can see it's not perfect. Best would be to just convert this vest to female - remove all male body parts, replace with female one, match vest to female body, then do wieghts uv_1 etc. Personally I really do not like to convert clothes, it takes a lot of time to make them look good

If you'll make it as an accessory then you have to move uv map somewhere where your vest won't overlap other clothes or accessories (probably have to make uv's smaller so lose a bit of quality), then make it suitable for female base body as you'll use other female tops and it's not going to match and change them like its whole top. Also make it double sided so it's not invisible inside, it's a lot of work too to make it works good

Hi. To clarify, it does not matter what category your item belongs to, this does not affect how it morphs.
When the breast area expands, there must be enough vertices for it to happen smoothly. Since the masculine chest has significantly less of them, it happens in a jagged manner.
If you were to put this vest on people of different breast sizes in real life, the fringe would not change its thickness. In ts4, on the other hand, it would, because that’s how it should behave. When breasts become bigger, all accessories in the breast area follow, otherwise they will clip

The only way of making it function more or less good is to manually reshape the vest to fit the feminine frame. You most likely will need to add extra edge loops in the breast area or/and reduce the effect of breast bones on the mesh