You probably have heard S and M. These are KY-esque* abbreviations. S means "sadism" and M means "masochism". Just like English, these personality types don't necessarily relate to anything dirty, and many people freely talk about who is an S or an M in public.
A slightly new term in this vein is ドN (do-en). The "do" (pronounced like "d'oh", not like the English verb) part is a derogatory prefix that means "totally". You can also say ドS or ドM. The N part comes from "normal." Together: someone who is extremely normal. How can one be extremely normal? Or abnormally normal? My head spins thinking about it.
Here's another thought: some people put themselves down by saying they are ドN. But you know what putting yourself down is in Japanese? 自虐 (jigyaku). But you know what that translates to literally? Masochism. "I'm not an S, I'm totally boring and normal," he said in a masochistic tone.
The most famous ドN I can think of is Hito Nami (who's name means "average person") from Sayonara Zetsubo Sensei, who often yells 普通って言うな! (don't call me normal!) Obligatory video:
I may teach you some more naughty words next time.
* Other talk of KY and such is in this post.