Having manners or (often excessive) mannerisms. (adjective)
Examples of word mannered
... and I suddenly realized that calling a singer "mannered" is just a way of concealing a certain laziness of opinion.
He was well mannered, that is to say well learned and induced in the sacrifices and works of the temple, as it appeareth in the beginning, in the middle, and in the end.
"My hunch is that the actor has drifted into a kind of mannered inwardness, either to suggest the otherworldly nature of Prospero or because he has simply become bored with the role [â€¦] But almost everything about this Tempest is disappointing."
It likes to present itself as quite 'mannered' in its approach to poetry but it often becomes a forum for the crudest vocalisations within that, and really because of it, as if shining the poetic silverware also meant locking it off from the thieving maids.
Meanwhile, living in Cambridge and knowing a very large number of Unitarian Universalists and various lefty folks, I can attest that not every liberal is "mannered," "self-critical," or "pensive."