Safety date is a person that accompanies you to friend's or family event, in order to a) give the appearance that you are seeing people and not isolated from society, b) avoid being set up on blind dates by well meaning friends.

Safety date（暫譯為"臨時伴侶"）就是去參加朋友或家庭聚會的時候臨時帶去的男/女伴，這樣做的原因有二：一是為了讓人們看到你并沒有讓自己與世隔絕，還是在跟人交往的；二是為了杜絕朋友們善意安排的相親的活動。

For example:

Jack brought a safety date to his aunt's dinner party. He did this because his aunt considered herself an "accomplished match maker."

杰克帶了個臨時伴侶去參加她姨媽的聚餐。他這樣做是因?yàn)樗虌屢恢弊栽倿?成功的紅娘"。