Ain't it kinda, " funny,, when a guy fucks around with another woman and his woman finds out shit happens.. BUT when his wife fucks around, You all get the drift here ????
HIstorically it's been used to denote an appreciation for, or interest in, sex with man's best friend ;o) Not in every case - some girls have them cos they think it looks cool or edgy or whatever, but yeah, it traditionally was code for some woof woof loving lol