That's no friend.

Does she act like that in the official stories?

r1c47 said:

That's no friend.

Does she act like that in the official stories?

No, of course not, haha~
However, in the few first CD's, there is some sort of...distance between them. That's because they have different points of view of the truth (Merry being a complete subjectivist, Renko being a complete objectivist.). In the first CD, you see how they call each other's eyes "disturbing".
But it changes slowly, and you can see that plainly in Retrospective 53 Minutes. ("We'll have a great time...Because you're with me, Merry")
Their personalities still clash from time to time, but you know...It's nothing quite like this!