hermself
A pronoun used when one does not wish to disclose gender by using "himself" or "herself" but when "itself" is too impersonal, and "themselves" is plural.
The celeb was so full of hermself
hermself
The pronoun to use when gender is non-specific or when one does not wish to identify a specific gender. When "himself" or "herself" is too specific, but "themselves" is inappropriate because it's a plural.
Tam is full of hermself.
hermself
A gender neutral pronoun, for when one does not wish to disclose someone or something's gender, used by people who refuse to acknowledge "themselves" as singular.
That person really needs to watch hermself