The Dawnguard (AKA Fuckbucklers) are a faction who hunt Vampires. Fün Tits tumultuously tries to joins them, however, her intention isn't to kill Vampires, but become one! Her plan is to bite her zombified love Astrid and make her live once more! Eventualy, the Dawnguard ends up attacking Fün and her travelling buddy Serana because, well... they're vampires.
"Have no head, will travel."
The motto is a perfect fit for the faction, for when their heads are chopped off, they do roll downhill for great distances, disregarding any obstacles that get in their way.