This thread was created for me. I'm that damn sexy. Give it up, people! J/k 
I don't have a sexiest anime moment, I've seen too many to consider just one part from one anime when I know there are other sexy favorite parts of different anime I've seen.
well l'm still saying, Chizuru and her boyfriend alone moments are probably the sexiest that came lately into my mind, those are really pervy sexy echii scenes, especially the ones at school music room where she gets naked, l was like LOL, l mean she was aiming for him all the time, and willing to do anything for him, l think a girl like that (not as pervy like that) is a true treasure, tough l don't think l would want my GF to be as echii as she was.
as for the best scene (normal scene) in all anime, l think it's when Chizuru talks with her brother while clipping her toe nails, l have never seen in any anime a casual scene like that, it just won me.