Dark eyeliner, if it's worn all the way around the rim of your eye, will actually make your eyes look a lot smaller... If you don't wear it around the entire rim of your eye, it will look feminine. I think your best bet is to steer clear of the eyeliner all together, and just focus on your clothes and accessories, if you really want to be seen as "emo..." Although I don't really understand why you'd want to. But to each their own. :) Good luck!