Special item sets look good together and they are useful for your business as well!
All special set items boost a food category and when you bring together all pieces of a set, you get a bonus buff such as 3x tips from customers! You can buy special set items using "Favor" which is a game unit that can be received from various actions such as catering bonus orders, celebrity level up rewards, e-Business gifts, etc.
Once you buy a set item, it goes to your inventory and you can place it from there. And if you sell these items, you can buy them for FREE again later!