Not a bad story, what there is of it. It was at +1 when I found it, and I'm leaving it there, because while it was decently written it was also very simple. A good drabble is a little like a good poem, in that you have to pack a lot of punch in a very few words. A good drabble is surprising, or emotionally powerful: a profound moment. This story was just a boy dreaming about a girl. The setting was fairly interesting, but all the other possible complexities were missing. The relationships between Roxas, Namine, and Axel are not this simple in canon. Of course, you don't have time to explain all the subtle details - in a drabble, you want to go for little hints. An expression on Axel's face, a sentence or two referring to how Roxas and Namine met (remember, it's not entirely clear in canon that they even did meet until Twilight Town, and remember Namine is a captive) things like that. In fact, for a drabble about how someone feels, you've managed to entirely avoid describing any sort of emotion, or even the absence of or Nobody-ish disbelief in one.
You're not bad as a writer, but your story needs more story in it.