I hate this ship.
I don't have anything against gay or bi women,I just don't think it would be possible for Mabel to be this attracted to Pacifica and the opposite.
Also,can we take a moment to remember ALL her crushes?!?
See any girls?Nuh-uh,I don't think so.
Well,we don't really know much about Pacifica and her love interests.(if you don't count her love for Sev'ral Timez).
I don't want to say that she would never fall in love with a girl,or Mabel specifically,but I would see her falling in love with Dipper,which leads us to Dipcifica.
Now,I will write about Dipcifica next time.
So,in conclusion,Mabel and Pacifica would propably be best friends,not lovers.
No offence,but it's more propable for them to be the kind of bffs which go out alone together or go to the prom together as best friends.
That's all I had to say about Mabcifica.
It gets a 3/10(3 because that's one of the lowest I can give to such a famous ship)