I think it’s funny that you named your robin, Robin. Why don’t you just call your girlfriend, Girlfriend.
Does anyone remember the movie Bounce with Gwyenth Paltrow and Ben Affleck? His name was Buddy and so was her dog’s name. Her kids wanted Ben’s character to change his name to Darth.
My daughter’s father brought 2 cats (mother and daughter) into the relationship- Katie and LK (Little Katie). Katie had a really skinny rat-like tail and LK, despite the name, was a bit chunky. I started calling them ratty and fatty. It stuck.