Oh... God... When Fanon Sans dusted away... you finally killed him... but you see his Soul hovered on his dust but... there's no phase 2 or some Plot armor Bs? You then grab it and see that it's beating very steady and strong... You still wondering why isn't there Plot armor bs... but you quickly push it away... However when you killed Asgore and Flowey... Wait there's no Chara? She supposed to appear in Genocide route but... it Seems that Sans killed her... guess you are now alone... with his Soul, when you cross the barrier... you see a surface and exit of the mountain as you exist... the beam of Sun shines upon you... As you hold his Soul...