I was pretty sure that being "Dragonborn" meant that your character has the soul of a dragon, or that he can simply speak the language. And the Dragonborn can be any race, that's confirmed, and the Septims are Imperials. How does a Khajiht come from a line of men? Or a Argonian? That's (probably) not possible, let alone likely.
So basically, your guy isn't from the Septim line. I think.....
They aren't, how many times will we have to say this.
It's like every week, "Dragons from Akavir! OMG", "We are Martin's kid! OMG"
Dragons are tying to destroy the mortal plane. There is no negotiation.
"Hey dragon why are we fighting?"
"My god told me to."
"Well don't, he is a jerk."
"You know your right little one. I'm going to tell Alduiin to back off. How mad could he be?"
... And we never heard from that dragon again. :shakehead: