*purrs* Oh, very nice. I'll admit that, at least at first, there was a little ache in my heart because you portrayed it beautifully as being that Sephiroth was, say, listening to them going at it on the other side of the wall. As if they didn't know he was listening in, and he was being all alone and lonely.
Then when it turns out they were essentially performing for him...mm. Nice. ♥ I had a shock at Genesis' line, a sort of "Ohshithefoundout!" moment. Then the second sentence came, which prompted a confused noise, and then enlightenment hit.