The more they interacted with each other, the more they became confused: some ways they were acting weren't as they normally would. Some of their memories which were rock-solid began to shift. They knew things they shouldn't know, and things they should know they were not remembering.
Their other friends around them, before even they do, began to suspect that they may have once been the same person--and as it turns out, they later find out through an accidental fusion that is in fact the case: they are, together, a magical girl. She split off for reasons they can't quite remember, but which vaguely involve protection, most likely, that of others.
The memories of others were altered slightly to accommodate for this, with them naturally building up once they had that base to be legitimate friendships, even family. (One of the girls was an orphan though. After the knowledge is revealed, it's theorized this girl was the 'split', and that the other girl's family is the original magical girl's family, just with their memories altered to be for the split girl rather than the original girl.)
This, alone, would be a fascinating concept, probably worthy of a story. But for me, there is a natural, obvious, deeper meaning to this dream, and that's obvious to any who are binge-readers or long-time followers. (Or, those who just so happen to have seen me as both names and know that I am both of them.) Basically, I think that dream was more or less my representation of Ranger and mastina: how they are two different entities, different people with different experiences and even different friends, yet part of a greater entity, and work together out of necessity for this force that is greater than both of them.
And that's why the dream was so precious to me. It gave me the feeling of me still being alive--all of me. Not just half of me, because that's been a bit of an inner fear of mine, not one which I've expressed. I've been worried that Ranger was dieing. I've been worried that she's slowly been fading away. But no. She's still there, as strong as ever, even if she isn't making her presence known to others as much as she used to. That makes me happy, that makes me glad.
She's a part of me. I don't know how large of a part. I don't know what exactly she is, and what exactly I am in relationship to her. But we're both there. We both exist. We both have a purpose. We might not know what said purpose, exactly, is, but we know it is there.