[Zanibas]

Spoiler for @OpenDoors:

But consider what lead up to this point...
-Witness of groping
-Witness of Kyousuke and Kirino on a "date" at Comiket
-Witness of a confession of "love"

Of course she's going to want to deny this and call him a liar, and she probably wants to know this is true. However, considering what lead up to this point, she may have doubts still. Honestly, you CAN interpret this scene in many respects, but that's part of the beauty of the scene, isn't it?