So, I know I'm probably going to fail at asking, but: do these two girls belong to some series in particular?

There's a Youtube Stepmania video with them as the background(non animated). Tried adding the tag but apparently there aren't any others of it so maybe I'm mistaken -removes tag-.

I thought they were supposed to be Exit Trance's rendition of the girls who made the caramelldansen.

Hmm. Interesting. Had hoped for actual characters, but good enough for me! Thanks KnightBlades and Fang-tan.

yea, they are the anime characters of the caramell girls.