Sly's activites

Recommend me something magical FL or swordwomen mc

Please help me find this one manhwa that is set in a cruise ship. It's a bunch of students that received a anonymous text or message that they can win $10,000 or smtn but they have to meet with their old classmates (high school).

I'm creating this list because i've read many incest manga's intentionally or unintentionally.so i thought of creating a list. 
True incest ( Blood related sis x bro) 
step bro x sis
step father x daughter
uncle x niece  
 twincest