this is the crucial reason why chinese eat dogs
ancient chinese culture think dogs is cheap, lowly because ancient china is agricultural country. not the price, i mean the value.
look at those stray dog. thin, illness, drooly, dirty, disgusting, sickness. they just know how to Ingratiate human, and do not have self-esteem. they are 贱的 like the position of bitch but without the licentious meaning.
so 狗男女 means those couple without morality(especially chinese morality-三纲五常、礼教)
狗东西
你这个人特别狗
狼心狗肺
蝇营狗苟
狗嘴里吐不出象牙、
狐朋狗友(those 不三不四的friends)
狗眼看人
狗屁不通
狗仗人势
人模狗样
there are so many 成语 having story behind. you can try to search in website to know.