In the world of Yorktown, hydras have a sort of hive mind, where the body is like the central computer in a network while every head is like other computers in the network. Everything done on them is accessible to any other in the network if requested. All autonomic functions are handled by the body.
Thanks to modularity, even detached heads have access to that central mind, albeit at the same “speed” as an old cellphone. So here we have R7 and S12 both giving up one of their heads and necks at the Chopping Block Bar, essentially acting as bridges from one to the other, keeping the sister always in touch.

Any questions don’t be afraid to ask ^_^

A great Snektember pic drawn by  andifferous