Cluster B refers to the category of personality disorder in psychology that contains narcissism, borderline, antisocial, and histrionics. Gwen thinks it should be called Cluster F... because this cluster really causes havoc and trauma drama wherever they go. Join Gwen on her porch as she breaks it all down for entertainment purposes, not diagnostic or treatment, with more of Nihm's emails. Bring your beverage, but caution when drinking because this tale will cause a spit take or two!