Glorfindel had to smile at the easy willfulness with which the young, spoilt son of Oropher sat down on the edge of the window and crossed his hands over his chest. 

The descriptions of Thranduil that you give are probably the best.

"“You are a nuisance, ernil-nin. But the saving grace is that you are one golden nuisance"

Now that was so true! Hot and steamy, not your usual style, but it fits in perfectly with your universe of the song of Sunset.