well, not my concubine, but possibly yours... Apparently Chongqing Normal University and Southwest Normal University(both in CQ) have recently banned their students from becoming mistresses, escorts and having one night stands reports The Shanghaiist(read the full article here).  Students found in violation of the new policy risk being expelled form school.
 So if you have any feelings whatsoever for that co-ed you've been eying, and don't want her education put to risk, the least you could do would be to make sure to have just one more date.