Many of the games feature random NPCs casually walking around who happen to be dressed like Playboy Bunnies. They are especially seen in bars.
The "Puff-Puff". In battle, some characters can learn it, and it causes enemies to miss their turn, whereas male characters who can learn this ability cause damage instead. The player character(s) can usually also receive this from a female NPC somewhere in the game. As a Running Gag though (and perhaps to keep a lower rating), the player is almost never shown exactly what a Puff-Puff entails, with the game usually employing a Fade to Black or Relax-o-Vision — and the times they do show something, it's more of a case of that particular game putting their own humorous spin on the subject to subvert the player's expectations. For instance, DQVIII shows a bunny girl performing a Puff-Puff with the traditional Fade to Black... and then revealing she's actually using a pair of held slimes.