They had been hanging out together since they were young, but they may have gradually stopped taking each other seriously.
He is very coquettish but others don't know it. She is very naive but has her own ideas.
The two often bickered.
He said: "Can you be more careful? How old are you? Sister!"
She said: "I've grown! Why do you still want to see it? You're so horny!"
Him: "..."