One Hundred Nights summary:

Orphaned at a young age, and barely scraping by, Baek Hoyeon. After ghosts have been finding their way to Hoyeon, night after night tormenting him, he eventually goes to see a shaman. He is shocked after being told that 100 ghosts are haunting him. With his life on the line, he has only one choice! “…You have to do it with each of them. That is your only solution.” The only way to survive is to have sex with the ghosts! All 100 of them!! And then he meets Chwadan, someone in a similar position as him. They come to an agreement; Chwadan will become the vessel for the ghosts and vanquish them together. With the thought of wanting to live to see another day, the two will have to spend 100 nights together…