is it like do they get to get freaky with anna too? or is like a ntr type deal idk cus i didn't try any of them

Sharing means the other characters will fuck Anna rather frequently, and at least in older builds Adrian would be fucking her in the shower every damn time she took one, so you could never get the Anna scenes with just the MC.

Basically you'll start stumbling into scenes with Anna having sex with the people you chose to share with, you can join, leave, or just watch.

Not cuck. Netorase (Something like that), corruption and sharing like a bitch sometimes. Don't worry not is NTR for you.