The demo is a large portion of the game.
The full version features 3 co-headliner songs (with unique boss mechanics.), 1 more openner song/character, and the final boss.
Total of 5 new songs. (Final boss has multiple phases/animations)
It features a few additional side animated Hscenes (in a similar manner to the home tent animations)
It brings a Gauntlet mode (A challenge where you play through all characters back to back with limited modifiers), and a few more features, and some more pin ups.