A tsunami is an alcoholic beverage containing a lot of alcohol. It’s 3 different kinds of rums, pineapple juice, and grenadine. It’ll hit you like a tsunami though. This alcoholic drink has a kick to it.
As you lay on this beach, the alcohol keeps coming down a chute (しゅ), straight into your mouth. You can feel the sand in your toes and the alcohol sliding down your throat from this special tsunami chute.