This is from Aya's dream about her brother.  In 
this particular sequence, she's sees the back of 
Aki.  When he turns around he's not her brother, 
but the rather nasty Mikage.  Then all of a 
sudden he turns back into the real Aki, friendly, 
cheerful, and sweet (not to mention terribly 
FWINE!) ^_^.  I adore this cel so much there are 
no words!  To me it's the perfect cel of him 
showing his true self...well...next to Twisty's 
pan cel that is ^_~