Lila
"Know that he was a person once. He may still be for all I can tell. But so be it. It has been some time since Andral 'died', so I doubt there will be an easy trail to follow."
Carmen
"And at one point I was normal Argonian living in Skyrim." He says, "Now I hunt the undead for a living." His posture shifts to be more straightened, "I've hunted harder game. I'm sure a crotchety old legionnaire would be no trouble."
Lila
"Do be careful. Keep in mind he, albeit with his brother's aid, managed to slay a vampire even though they were ambushed and unprepared to fight such a creature. Whether it was luck, simply a weak vampire, or a genuine sign of skill, I cannot tell you. Still, be careful. He may be old, but he's clever. Cunning."
Carmen
"Heh, it won't even get a blow in." He says, "Undead know to fear my presence, and Lady Merid grants me her strength. That beast stands no chance."
Lila
"What good is strength without the wisdom to wield it? Oh, but no matter. What do you ask for in return for dealing with Andral?"
Carmen
"I have the wisdom required to destroy the undead, that is all I need." He says, "The Dawnguard ask for nothing in return, although donations to our cause are not unappreciated."