I can assure you that here on the other side of the pond, I've never heard the word slapper before, compared to other UK slang words like "totty" or "wanker".

I can assure you that here on the other side of the pond, I've never heard the word slapper before, compared to other UK slang words like "totty" or "wanker". So, when I read the article, I merely parsed it as "a person who slaps", like a worker is a "person who works" Enjoy :)