I’m mildly obsessed with the idea of one partner falling in love with Peter (in my head usually Steve or Nat) then bringing Bucky along for the ride.
Like Bucky loves his partner so fucking much that he’s happy for them to have him as their boyfriend.
Peter meanwhile is freaking. The fuck. Out. Bucky is Bucky. Peter legit doesn’t know if Bucky wants to kill him or fuck him.
And Bucky’s partners are super affectionate with Peter. And Bucky’s gentle with them, and Peter too. And he’s just like, you wanna date, do it. Wanna fuck, off you go, I don’t mind.
And Peter had no fucking idea where he stands despite reassurance until one day something happens and Peter gets hurt. And Bucky goes feral on whoever dared hurt his husband/wife’s boyfriend.
Then he shows Peter just how precious he is.