Its a good thing, it means that your hard to figure out in a good way which means she probably wouldnt mind trying to - youre a bit of a challenge.

I think in the photo you just look like a normal guy, but you seem to be thinking about something - maybe thats why she said mysterious?!

Don't really see how that photo makes you look "mysterious". Just looks like a photoshoped selfie.

But yeah girls like mysterious.

It is a black and white photo, taking a picture of **** and instagraming it black and white would make it look mysterious. >.> normally? your facial features suggest not so mysterious. but she is hitting on you and trying to make you feel better about yourself and like her more for her flattery, you missed to point