Five students, 3 women and 2 men, was ashore a remote island, survivors of their sudden ship sinking. Finding themselves in this extreme state instinct and conscience intersect and collide! Crossing thoughts, feelings of love and hate mixed with trust and betrayal. A story of uncontrollable libido and murderous intent...

Note: For those interested, manga has been adapted from this light novel which was 2 volumes (in Japanese).
The original r18 web novel can be found here here