So theres a story i was reading about Snsd taeny vampire post apocalyptic story. Of Taeyeon as survivors try to survive as the vampires rule. Taeyeon is attacked by vampire and Yoona saves her life. N run into TIffany who is with a group who are vampire hunters. Later it turns out Jessica is Taeyeon sister not biological but by Yoona who is both their vampire mother.

Idk if this is helpful but i cannot remember the name all i remember is what happened in the story.