Two current Beijing subway ad campaigns for two well-known English schools, Wall Street English and English First. (Sorry for subway glare+reflection in both pics):

Both are a little strange, but to me the first one is strange/eyecatching, whereas the second is closer to strange/creepy. The theme of the second, bondage-toned ad is having a 24-hour always on-call private English teacher. On the other hand, this campaign seems to have been running for years in subway, taxis, billboards, etc, and the English First school is a big success. So I guess it must work with the target demographic, which does not include me.