@ midknightcake In the first few chapters it's established that mermaids and mermen used to lure humans down in the water to drown them by singing, (they were called sirens then). But later on they stopped drowning people and so when Yoongi went to visit his friends in the end, Y/N was drawn into the water, not by will, but because her mind was telling her she needed to hear him sing again. When sirens sang it was putting humans in a kind of trance, so the humans didn't really control what they were doing. I hope that clears up all the confusion, if not, I'll try to explain again :)