Basically a liquid such as alcohol, milk or even water is attached to the top of the device, which acts as a neutral color liquid. The various tubes at the back are then attached to bottles of various colors, for example you could use rose syrup, or grape juice, or pink guava juice, or a bottle of Gatorade. As the liquid at the top flows (whose flow rate can be controlled), you then type in the various letters which will then draw out the liquid from the other bottles.
For example you could associate the letters on the “keyboard” (which are actually syringes) with its drink, like A for Apple juice, O for Orange juice, L for Lime juice, so on and so forth. By pressing the letters, the colors will then form into the various alphabets that you pressed in the white piece of plastic on the front, which a commenter on YouTube has amusingly referred to as an LCD – Liquid Cocktail Display.
It does not appear to be for sale, but if you want more detailed information on how it works, you can check out the video below for a demonstration or head on down to morskoiboy’s website for more details.