Why the Ginny/Draco couple works.
aka "Why Ginny is the only girl for Draco."
Let's start out with personalities. Draco is bad. He does not seem to know when to quit it; one of his favorite hobbies is probably making little first years cry, or pushing Ron over the edge. Ginny is good. She has a temper though, and seems to know how to handle just about anything.
Ginny can control Draco, and make him good, and keep him in check. Why can no one else be with Draco? Pansy would egg Draco on (as would anyone else in Slytherin), and he would be very, very bad. Draco would probably hurt anybody else. Ginny has just the right personality to keep him in check.
Okay, you might be looking for proof or whatever that Ginny can actually control Draco; after all, in the first and second books, she was basically a pipsqueak. (A/N: I don't really like this, but that's just kind of how it was… At least when it came to Harry which was mostly all that we saw of her then.) Right-o, I forget where exactly, but in the 5th book Ginny put a really good Bat-Bogey Curse on Draco. Personally, that and her quick thinking with the whole bit about the garroting gas ("that's because it's colorless"), I think Ms. Rowling has given quite enough proof that Ginny can handle Draco.
Okay, actual romance between the two… Fiery red head + arrogant blonde = blonde no longer arrogant, which I think would make him somewhat of a ladies man, which I think would have Ginny not set that curse on him, which would probably make them the perfect couple! ^_^ That's how I see it anyway.
Conclusion: Draco needs to be with Ginny, even if Ginny doesn't need to be with Draco, and therefore the Ginny/Draco couple must exist, or all hell will break loose on Draco's doing.
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Author's note: I think I'm going to put other couples in here too, but I need reasons why they work, so it'll probably take a while... heh ^^; Also, I'm *not* doing Hermione/Ron because they're the most obvious couple in the whole book, and I don't feel I have the need to explain it, even if some of you don't like that couple. Please review! ^_^ (And R&R&R was done on purpose; Relax in chair, Read story, and Review story! ^^ er.. actually it isn't really a story… O.o I'll have to work on that one.. Any suggestions? The whole lock-em-in-a-room-until-they-fall-in-love bit is getting kind of old…)