[Perhaps what she's doing is...throwing him a bone, heh.

Sayori blinks at him a few times, wide-eyed and blank. She processes this, and blankness turns to astonishment, her eyebrows in a high, surprised arch.] That's amazing! I can't believe I didn't think of that!

You're a genius!! [She's entirely earnest about this, and gestures a little with her hands in Emphasis.]

It's pretty gross, but I bet your idea would work!