These mermaids are demon mermaids, they are dangerous and will drown their food, do you know what their food is? that's right, us. They will not eat their companion however they will return to the ocean once a week to feed. so keep this in mind. there is only one offering you can give them an that is blood. they can and will do SO MUCH for their companion it's scary, but you gotta get over the fact they consider us food.