I have to say yes. Though my answer is probably bias, because I've been fangirling these two as yaoi. Brian can't hold onto a girl, and has been looking for someone that is intellectual. Stewie we have seen with girls, but we have also seen him liking guys. It would just seem a great match for a couple. They would fight, but what couple hasn't? In my mind, Stewie does love Brian THAT way.