Bitch here, like Man, has no singular article directly when used as an abstract noun. Seeing that dogs are man's best friends and many other famous sayings.

If you want to directly call names "fxxk you" and express your complaints, use "fxxker mom", which is similar to damn, nonsense and other usages (Joey also created the phrase "kisser mom" by analogy in an episode of Friends).

It is not recommended that the landlord entangle the grammatical structure of such proverbs too much. Since the landlord often watches American dramas, it is not bad to understand it as a hobby.