Well then , welcome to the Sixth House ! Prepare to embrace your inner Clarinet <| sep |> If my memory serves , Harkon tells the player if you need to feed like baser vampires . implying that it ' s a choice but Harkon at least doesn ' t feed . Serana for sure hasn ' t fed in a long while , and she doesn ' t seem to care that she doesn ' t get to feed while adventuring with you . Really the only reasons to feed that I can think of are 1 to curb the effects of vampirism if you a don ' t want to be a vampire or b want to be a vampire but need to do mortal things and 2 if you just like the taste . The second mostly applies to those whk have embraced vampirism . The first to both depending on the situation . If you want to be a vampire there are still reasons you might want to dampen the effects . You could for example just want the immortality but not want the other stuff like burning in the sun and looking feral .