The Tully's should now be released with Frey's death and Edmure reunited with his wife and child. Edmure should be bound to House Stark who will need every sword possible for their fight against the white walkers.
Walder's eldest son Stevron is still alive. Idk where he is but alive nonetheless. Plus the Lanisters still control the riverlands. So unless Arya releases Edmund (which I doubt she did) idk what will happen to him. Perhaps Jon will come seize the Twins and restore Edmund so he can a.) have the Tully's and b.) hold the bridge that cost Rob his life. Although Jon will be fighting a different war and may not value the bridge.
But… can the Lanisters even afford to protect the Twins anymore? The Lanisters are a bit beat up. They've been in a lot of battles semi-recently and are broke. They also know they've got Dany and her dragons coming soon. Plus Cersei just dissolved their strongest ally when she blew up the Tyrells. So the Lannisters are basically fucked. Their enemy list now contains Dorne, Tyrells, Starks, and of course Dany. Three of those houses are allied now and if Dany brings the Starks on board with the rest then the Lanisters will be getting fucked in every direction. Oh yeah I almost forgot… Tywin was borrowing money from the Iron Bank… hmmm they're fuuuuucked!!!
I'd love to see the Lanisters completely wiped out and Tyrion given back his birth right by Dany and take his place at Casterly Rock. It's what he's wanted since after the Battle of the Blackwater.
There's a great site for GOT info really helps you link all the moving parts and learn the back stories.
http://gameofthrones.wikia.com
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