>>105410521They're not similar at all but the title made me think of "The Person I Loved Asked Me to Die in My Sister's Stead". The opposite of your title kinda. It's sort of meandering right now it and absolutely girl-coded but I quite like it.
I think I've seen the one you mentioned, but never gave it a go. There are so many villainess stories that I basically just go for which one has good art at this point. I'll give it a read!