YEAHHHHH was confused as well even back during chapter 11 when the bad guy SAID her name was Ouyang Pei but then very next chapter she's MC's student? I by passed it at that time cause thought tl or author put in the wrong name. (Especially cause chick looks the same as his student)
Then chapters 12-13 further confirmed my suspicion of "O just the wrong name". Since he said my student and she said master.
However now? She's a stranger. Definitely not his student. Definitely just met that once. Could of been passed off as him helping her because he's a fair just dude or perhaps even just getting revenge for almost getting run over by the car. BUT the moment they started saying student shit just got ducked up.
I'll imagine those chat bubbles say Random stranger who saved me.