While I am not sure this is a totally appropriate question for an education forum, I too am a gleek and can appreciate the talents of Darren Criss.
Having seen him perform live, he has a great ability to entertain and has great ability to dance and sing. Because he plays a gay character on Glee, many people think his is gay. However, in an amusing interview I read from him, Criss said that he grew up in the San Francisco theatre community...and when he "came out" as being straight, his friends said, "Say it isn't so!"
As to why he looks good in pink sunglasses...the author at this link might have some answers.
Because he's hot in general, of course. <3
-Your fellow Gleeek. <3