Hello Kitty Café is an interesting place. It's aesthetically pleasing - ok, extremely adorable - and has desserts and drinks on offer to match.
Every opportunity to incorporate Hello Kitty is exploited: think Hello Kitty shaped cakes, Hello Kitty drinking glasses, Hello Kitty coffee art, and Hello Kitty bow embellishments. Yes, it's a bit of a novelty, but the visual appeal of the menu items (already fantastic) don't hinge on it.

A cappuccino at Hello Kitty Café.
In the era of the artisan café, it's nice to have somewhere a little kitsch open up. The only downside is the desserts: they look beautiful, but the taste didn't quite measure up. On the upside, the drinks were as nice as they looked.

The 'pot plant' dessert

Mousse
It might not be suitable as your regular coffee stop, but it's worth at least a visit if you're in the area.