the first fight reminds me of a story i was told by a co worker in australia,she was a new zealander probably pretty tough named trina,that was short for a name she was too embaressed to say,so i guess not katrina,anyway she said that when her bf and his mates used to play cards,another mate used to bring his girl & the 2 of them just used to just fight,once in a while the boys would look up from the game and check that it wasnt getting serious & it never did
this scene seems to be something similar that just got serious enough for the boys to be distracted from their activity,whatever it was,the girl with the shorts seemed to be winning any time it got more serious,surprised it ended with the other girl appearing to be on top