Mr. Garrison

"Genetic engineering erases all of God's mistakes, like German people."

- Mr. Garrison (quote added to showcase his vocal racism, which is often played for laughs).

Mr. Herbert Garrison is a recurring character in the adult comedy series, South Park, he is notable for being one of the most complex characters in the show and has varied over the years from a jerk to a full-blown antagonist and back again

Biography
Mr. Garrison is horribly racist and homophobic despite being gay himself - he was also a somewhat cruel teacher and enjoyed humiliating certain students, he was also a vindictive character and once tried to sue the school for prior mistreatment by using his as-of-then openly gay partner, Mr. Slave, to perform grotesque acts in front of the students with the aim of being fired - this backfired horribly on him however as he was hailed a hero due to "political correctness".

Mr. Garrison went through a sex change operation, renaming himself "Mrs. Garrison" (despite not being married). His vulgar nature never changed, in fact he became arguably worse: seeking to have an abortion (with abnormal glee) and treating Mr. Slave extremely badly as s/he reverted back to homophobia, later Mr. Garrison tried to outlaw gay marriage to spite Mr. Slave when he tried to marry Big Gay Al (showing once again his vindictive side).

Mr. Garrison is also famous for being insane (albeit his insanity is often played for laughs) - having an alter-ego in the hand-puppet known as Mr. Hat: who sometimes plays out some of Mr. Garrison's darker fantasies which he claims to be repulsed by (such as when Mr Hat was a member of the Klansmen).

Despite claiming to be repulsed by Mr Hat's involvement with the KKK Mr. Garrison engaged in very similar acts himself when he tried to drive away all the "richers" from South Park in one episode - becoming in many ways the very thing he professed to hate (this once again highlights Mr. Garrison's often chaotic way of thinking, possibly due to his split-personality).

Although not villainous in the sense of harming another being (at least humans) it was implied in an early episode that Mr. Garrison, in addition to being a suppressed gay, also engaged in bestiality - which (if true) would further complicate his already infamous sexuality-issues.

When he went back to being a man he started to become less insane and started to act like a perfectly sane teacher.

Personality
Mr. Garrison has shown to be a vindictive, abusive, homophobic (ironic since he's a homosexual or at least bisexual), as well as racist individual. He loves to force his beliefs on others, it's his attitude which led to a post-Apocalyptic future where three warring Atheist sects are emulating his beliefs. During the Christmas Specials, he freely calls Jews, Hindus, and Muslims heathens who don't celebrate Christmas while saving his greatest amount of vitriol for the Japanese.

He was also abusive towards his lover, Mr. Slave, to the point where Mr. Slave left him after the sex change since he didn't care about how Mr. Slave would feel and only thought about himself. Mr. Garrison always has had a trouble with empathy to the point where it becomes apparent he lacks it, becoming nothing more than a sociopath near Cartman's caliber.

This is shown explicitly during Follow that Egg!, where Mr. Garrison tries to 'take back' Mr. Slave and gets enraged that Mr. Slave has moved on is in engaged to Big Gay Al. He believed he was taking Mr. Slave back and thought that his old boyfriend only left due to Mr. Garrison calling him a 'faggot', ignoring that Mr. Slave said he doesn't like women and that Mr. Garrison never even consulted him before the surgery. To sabotage their wedding, Mr. Garrison turns the parenting exercise he gave his class into a rigged experiment to prove gay couples can't take care of children. And to this end, he's willing to murder people as shown in the final part, nearly killing Stan and Kyle when they show off the egg being perfectly fine.

Trivia

 * His relationship with Mr. Hat is very similar to The Ventriloquist and Scarface from the Batman series, as they both have a puppet that they claim to have a mind of its own, they both wear glasses, and they forced the owners to kill people.