obviously - it's a reference to a scene in tsukihime (the background and the text) in which the main character thinks to himself, "This chair. This chair. This chair. This chair." etc. for ages until someone wakes him from his reverie and he finds he's been smashing a chair against the ground for minutes. It's also a reference to a scene in Code Geass: Hangyaku no Lelouch in which, well, a girl humps a table. Har har har funny lololol.