There is the Dormire Sofa Bed that can lift up just like the one in the Lego Movie and 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. Your legs might dangle in front of the people on the lower couch so it might be considerate to sit with your legs crossed! And if that doesn't meet your needs, we have other innovative sofa beds for sale.
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
