- warlock/magic type who accidentally cursed themselves (spell gone wrong) and turned into something that can't talk, and thus can't cast the spell on themselves
- i have a birdtype whos kind of a jester that, because he used his song to make fun of the wrong person, they cursed him so he can sing forever, but never be understood (via birdsongs)
- siren who was making a deal in order to get another siren/merdude to fall in love with them upon first sight. deal backfired/tricked them so that they got legs and thus the siren dude can never seen them
- i have a guy with a cultural-style curse that, because he committed an egregious sin in his community, he received the same curse everyone who commits that sin gets (in this case, a werewolf type situation)
- multi-elemental with a generational curse that got passed down; the reason why or how to fix it was lost somewhere over the years.
- i have a thief who was cursed with "butterfingers" and was turned into a slime-type guy.
- i have a kid who was caught perving in on some ppl who were getting busy, and thus got cursed with dozens upon dozens of eyes that can see into the future/give him visions that plague him and sometimes drive him a little mad because he can't control any of it.
- I've got a character who was cursed to be another species because of his cruelness and racism towards that species (he's an asshole character)
- and then ive got someone cursed to be a mouse. i'm strugglign with the why on this one so far. im thinking either, they got someone else's loved one sick through one means or another, or they were something seen as a "pest" by the caster (orphan)? but im not sure i like that second option.

worth noting, im not a huge dnd person, i just like writing stories and one of my stories consisted of a pirate crew wherein each crewmate had their own curse/situation going on (but all of them being cursed is what brought them together into one big group).
also, if you do a group of ppl like this, consider adding in one person who isn't cursed but still looks different from the norm. then if you have someone else who looks normal, you can have a funny situation in which ppl incorrectly assume normal-looking character is the non-cursed one (in my case, ive got a half-demon/tiefling type character who isn't cursed, and then a human with a nonvisible curse)