So the latest comic, released today, suggests that Twilight's brother was a geek while growing up, and that he pursued Cadance while they were in school together. An amusing story, although I don't blame others for thinking a romance between a guard and a princess could have had more adventurous origins. I know some aren't fans of Twi's BBBFF for having a lack of strong personality traits, but then he and Cadance have simply been supporting characters so far, and have existed to help set up grand adventures rather than slice-of-life stories. They're not really there to be zany, or to move to the foreground of the episodes. We'll see how they're developed in Season 4, where these Equestrian Games seem positioned to give them more slice-of-life roles.