For various reasons the foreign affairs office here did once in recent memory make a survey of sorts into how many teachers, Chinese or otherwise, were dating students. In a school of a great many more than five teachers, five Chinese teachers were known to be in relationships with students. (I don't say "dating" because what Chinese teacher dates? Who knows how the relationships were viewed, I only know the numbers.)
And a friend, a student, was talking one day of how she introduced one teacher here to one student here. It was okay, she said, because the girl would graduate soon and both girl and teacher were local people.
And another friend is the girlfriend of a teacher, but not a teacher from here--they met in middle school.
That I'm aware of, no foreign teacher is currently seeing anyone. It seems the Chinese staff have a lock.