As you might be aware, in Italian, "j" (i-lunga) is not a regular Italian alphabet. Thus, unless it is a foreign word, "bonjero" would not make good sense in terms of a vocabulary in Italian. Additionally, the posed question seems to be quite gender-biased in nowadays community, unless you are solely concerned with expressing a strong despise towards a particular person in female gender. Based on the suggestions given so far, I would say that "stronza" ("stronzo" for male) is a good choice, because it can be applied to both genders (by solely changing the ending). "puttana" is somehow related to other roman languages in terms of its appearance -- "pute" (en français), and "puta" (en español, em português). "troia" is from "scrofa", which means "la femmina del maiale", whereas "cagna" has a meaning of "la femmina del cane". Anyway, although we have the right to know whatever knowledge, I personally suggest that you would refrain from using such terms unless you were in very exceptional circumstances. --- Good day. / Buona giornata.

Stronza or puttana

I quote Sony. Even if "prostituta" is the less unpolite word in this case.

the right translation is "cagna" that means "she dog" but in the figurative translation you can say "troia" o "puttana" these are two bad words...if you want to say iy in a more polite way you can say "donna facile" but it's not used a lot in the spoken language.