Reimu and Flandre look very uncomfortable :V
If it's the eyebrows, a neat thing some views on youtube picked up on was that he would move his eyebrows depending on the pitch of whatever he was playing in that one frame. That's one of the things that really impresses me about those videos on tha McGroove channel, there's a bit more detail in his vids than you'd pick up on at first.
Loved the OP nico vid, too.
