Nah, I don't think it works like that. It's more like, I will fulfill your wish, but....
I think it has something to do with the reincarnation thing? Like the original owner wished to start over, but she didn't have much life force and her soul is replaced by the current FMC, but it's it still not enough, hence the terminal disease. Or maybe not a disease, more like it keeps draining her life force or something.
Thanks for the chapter!
This is one of three things i think:
1. I can't remember since I'd have to go back and read it, wasn't it implied that she had the virus or illness that was going around or meant to happen. She's been coughing in previous chapters.
2.She shouldn't have asked that question (she got literally hit with a flag lol)
3. OR something like what was mentioned in the above comment.