Whoa, haha! Didn't think you'd reply 7 years later. That's the thing, though — Ranna always go way too overboard with her violence. Rokudou usually doesn't even knock his opponents out.Doesn't matter, his actions are still the exact thing he is telling Ranna-san not to take.
It is not like Ranna-san was going to start something she was just going to solve the problem through violence same as Rakudou is doing...