Na mate.
I had a good knowledge of gravure idols back in the day.
I've also followed the idol-group thing pretty-closely for a long time, Hello Project's Morning Musume and Tokyo Girls' Style being my favourites. The latter's now moved on to being an adult pop group but Morning Musume is one of the many groups Hello Project's kept going.
FWIMBW, it's the funky and disco songs that I like the most and these are the reasons I started getting into it many years ago. There was just nothing in the western-pop scene that competed IMHO. Generally-speaking the musicianship and arrangements for / in idol groups is top-notch and I've never listened to lyrics anyway so the fact that it's a foreign language hasn't bothered me in the slightest.