In the Walkthrough Katie Dom Route (Go to War with Katie) means MC dominates Katie (as for now; you can hit her or hurt her verbally) and Katie Sub Route (don't go to war with Katie) means Katie dominates MC (as for now). Theres the possibility that those Routes turn into the opposite in the next updates, as MC looks for ways to get back at Katie when on Katie Sub Route and to dominate her instead, as well as Katie could look for opportunities to get revenge on MC for hurting her on Katie Dom Route. I would recommend to play both and keep a save for each and check how the Story continuesThanks, sorry I had to make such a question with a obvious answer.
On another subject, when the walkthrough mentions dom route for Katie, is she the Dom or it the MC?