-Tripping-?? I really don't see how she could trip to both knock over the chair -and- end up on top of him like that. Either she climbed onto his lap and knocked the chair over, or perhaps she really -did- jump out of the screen, as redtails suggested.
Update: Ok, according to the getchu page for this game ( http://www.getchu.com/soft.phtml?id=125481 ), she's the heroine of the h-game he had just been playing, and she really did just suddenly pop out of the screen.......