The karaoke is nightly, at 9pm. As far as I know, yes, there is only a Japanese menu-- the sushi is excellent. Fun for a teenager to watch-- hmmm. Depends. I've done karaoke, and I think to get in the spirit of karaoke one has to do it oneself. Face it- most of it is pretty rotten, but if you've gone up there yourself you're a little more forgiving. Does the teenager want to sing? Just to watch other people you don't know karaoke all night is a drag, but if your party is participating, it is a different thing.