A Korean Dessert I've Seen a lot recently

Recently I’ve seen a watermelon dessert with a few variations but in general the base is the same. They take a watermelon and scoop out the insides and place it in a container. Sometimes they just add some kind of soda pop to it, it’s usually clear. Other times they add a can of some kind of fruit to the watermelon along with milk and the soda pop. I’m assuming the soda is some kind of citrus or ginger soda. Does anyone know what this dessert is? It looks like it may taste good and I want to try it but I’m not sure exactly what goes in it.