Raindrops been having a nice long sleep on a cloud, but she went without milking. Since her teats are more productive, they began swelling and leaking a bunch. First onto the cloud, which is why there are still bits of milky rain from it. After a while her crotchboobs have become big enough to go straight through the cloud and have begun leaking even more. As the crotchboobs’ swelling tries to keep up with its production, leaks became large sprays of milk, going down below like rain.