If the Cullens were to change partners within the cast of twilight I think we would see:
Carlisle x Charlie ft. Medical malpractice and a very toxic romance
Alice x Jacob (he makes her mind quiet)
Bella x Rosalie x Emmet ft. sperm donor Jacob
Esme x free will and an art career
Jasper x Leah
Edward x forever wallowing in his pity - though if Bella was still his singer i think Charlie would hunt him down this time and try to lock him up for stalking but Carlisle would end up stepping in to not lose his toxic yaoi test subject. And Edward would probably get chased out of Forks.
I won't write this as a fic but i thought it was a cool thought.
That polycule would be the most functional and well adjusted throuple ever. Bella would finally be ok. She would get turned into a vamp only after their kid manifested as a werewolf so that they could stay immortal together.
And also I need more toxic Charlie x Carlisle. "My vampire doctor wants to examine me and keeps pushing his weird religious philosophy on me and I think I get his point of view. He is making a lot of sense and... wow we are doing it on the exam table?"
