one of the KitKat series is the オトナの甘さ, Adult's sweetness. as its name suggest, since it's for adults, the chocolate is not as sweet, but not necessarily bitter. the most recent i tried was the white one. i'd say it's pretty similar to hershey's cookies and cream with KitKat's signature crispy bar in the middle.
a light tasting good snack
dark chocolate from last year