In ancient China, women bind their feet for cosmetic reasons, resulting in them not able to walk without help and walking in a shuffling gait.
Possibly this can be modified such that people do it for less stupid reasons.
Disclaimer: This is NOT a racist remark since I'm Chinese myself and hence entitled to freely judge Chinese customs. NOT sexist either since I'm female as well.
This really comes from an ancient Chinese novel. Imagine during the PCs' travels, they come to a place where the gender roles are completely reversed. What adventures will the PCs encounter in such a place?
A sentiment weapon that is very impressionable in terms of what is right and wrong, akin to a child. Currently, being ownerless, it is not very powerful. However, once it has found an owner, it can provide significant boosts to the wielder in an area or areas the wielder most desire. What adventures will this sentiment weapon go through? How will it develop itself in terms of power and personality?
The Lord of the Flies, the Muscimancer has studied magics that summon, control and otherwise deal with flies. The Fly Mage is an unwholesome character, also likely to have magics of disease, rot and pestilence up his sleeves. After fighting through his swarms of flies and his loyal acolytes and slaves, the Muscimancer reveals his final power, transforming into a giant half man half fly hybrid. He can fly, acid vomit, as well as continue to use spells, wield weaponry and command his swarms.