Understandable, who wouldn't want to befriend a kitsune if they had the chance to after all! As they say: Sharing is Caring.
TF Mastery unlocks are the most time consuming thing in the current public demo, at least if you want all unlocks. Getting all unlocks for a single tf isn't taking that long. Pretty much depending on the difficulty. Master and Credits can be gained a lot faster with many Modifications and Ferocity Levels turned on.
I think currently the Friendship System isn't in the public demo build yet but they will be added in the next public version. There will be 6 companions who you can befriend and able to take with you ona run. And Kitsune will be one of the People you can befriend.