An image came to my mind, I saw the Last Man as the product of the final, definitive loss of resistance and unconditional and irreversible surrender to 'duh, the obvious...'
This species, which can absolutely not be regarded as a full fledged human but rather as a creature reminding only in appearance of the human, lives juggled together as in a glass flask, fallen through the bottleneck (from where it may have climbed (resisted) upward to proper being) into the 'mix', the sloshy substance of self righteous popular opinion that is designed to undo this type of human of the last traces of his connection to natural reality.
The Last Man is typically of indefinite origins, city dweller, holds liberal views on politics but illiberal views on the matter of thinking - thought is perceived by this species as a direct threat - any sentence that suggests a consideration rather than an obvious fact is regarded as a deer regards headlights, or a rabbit regards approaching boots. When there are more last men present around the uttering of such a sentence, a most hyena-like 'hostility' is the assumed form.
If such a last man (often, women are the least, the 'most last') is given a platform of authority, s/he will ramble on, in a shrill and indignant voice in which one can hear the abyssmally ugly certainty of being in the company of masses of like-'minded' listeners - and utter two things: a heart consumed by hate and a mind entirely hollowed out or unused. The ugliest creatures nature has ever produced.