"Only because you've never had a girlfriend."

It's a shot in the dark, but Sherlock isn't the only one who can assemble evidence to reach a logical conclusion.

Evidence like, you know, how it would be pretty hard to find a girl (a decent girl, one actually worth his time, not a golddigger more interested in the Stark money) willing to date a guy who goes by Sherlock Holmes. But that doesn't mean he shouldn't try.