The Lego Movie popularized the concept of a Double Decker Couch from the lovable fictional home of Emmet. Did you know real life versions of Double Decker Couches exist?
There is the Dormire Sofa Bunk Bed that can lift up just like the one in the Lego Movie and can lock in place. The original purpose of this concept was to have it set up as a bed below and a bed up top, but you can adapt the idea to sit up top and below. Do consider your legs might dangle in front of the people on the lower couch so it might be considerate to sit with your legs crossed! Product link here: Dormire Sofa Double Bunk Bed Couch
There is also a triple decker couch, but more appropriately it was designed to be a triple sleeper. You can however use it to seat up top, below, and on the trundle. This one is customer ordered from Italy and you can choose your own fabric color. Product link here: Italian Triple Bunk couch