There are two, actually.
If you're custom belt (20k qi), you can buy an item which allows you to edit your belt to pretty much whatever you like.
The other is bounty text, which stays after someone has claimed the bounty that was on you (if person who created that bounty paid for bounty text, that is).
Note: you can't put a bounty on yourself, someone else needs to do it.
You can access bounty list via shop.