Kioku to Sora, Eege ~Umi ni Sasagu~, and Baroque were all really close, but I chose Eege ~Umi ni Sasagu~. It's such an amazingly beautiful song, and Tetsu sings it with such emotion, you'd think that he was in the exact moment that the song takes place.
Eege ~Umi ni Sasagu~ is one of my favorite songs ever, not just from Malice Mizer. And it has one of my all-time favorite lines in it *points to sig*. *sighs dreamily*...