"Under genre classifications," you say?
You might want to be more specific, dumbass.
Now, I'm going to go and say ANN and the Wikipedia article both class it as shoujo-ai or yuri.
Now you might reply with something undercutting the credibility of both. However, I find them more credible than random anon with poor grasp of capitalization, grammar consistency, and hyphen usage? Or failure of usage, as it were.