Second question, through the main quest Serana tells you that killing his father is necessary to stop the prophecy and Valerica tells you that Harkon wants to kill his daughter to fulfill said prophecy, yet when you acquire the bow Serana offers her blood (causing her no harm) and you are the first to shoot it at the sun (yeah, we're going to kill my father because he wants to blot out the sun, here you have some arrows soaked in blood to blot out the Sun ????

Maybe it makes perfect sense but I cant find it.