Flutie's replacement was Snyder, a man who serverely hates kids which does lead to questions about his choice of vocation. He does not believe in the way Flutie works saying it was the kind of "wooly-headed liberal thinking that leads to getting eaten." Well he's not wrong is he? Apparently he was given his job by Sunnydale Council who thought he was the man for the job.
He is also aware of the fact that Sunnydale is the centre of not-good activity, covering for a vampire attack in the school by saying the perps. were gang members high on PCP.
One thing he does share with Flutie is school spirit. He roped Giles into being in charge of the school talent show, and forced Willow, Xander and Buffy into performing in it.
This leads us nicely to Buffy. He certainly has it in for her. He made her organise a Parent-Teacher evening telling her that if it goes wrong she would be expelled, and he's always on the look-out for her to get into trouble.
During the first and second years we did not know how Snyder knew about the strange goings on around the school and Sunnydale, although he covered them up wonderfully: PCP high gangs (School Hard), backed up drains to explain the snakes in the cafeteria (I Only Have Eyes for You) and usually blamed Buffy for the goings on.
When Dru murdered Kendra and kidnapped Giles, Snyder found Buffy kneeling by the body of her friend and accused her of murder, and because she was such a troublesome influence the police believed him which forced Buffy to go on the run and Snyder to gleefully expel her from school.
The Scooby Gang had their own reasons for Snyder's horridness. Buffy thought it was because he didn't get at date at all in high school and Cordelia thought he was a little Nazi.
But Snyder certainly did cheer up with Buffy gone from Sunnydale High. In fact it even gave him a tingly feeling to refuse her back into school. It took a little 'gentle persuasion' from Giles and a letter of reccomendation from "Someone who isn't an English Librarian" to finally let her return.
We discovered over the course of the third year that Snyder was involved with Mayor Wilkins. He was the man Snyder always reported to and the police chief reveals that it was the Mayor that recoomended him for the job of Principal in the first place. The Mayor also has Snyder keep a close eye on Buffy.
Unfortunately, being such a loyal supporter of the Mayor didn't prevent Snyder getting munched on Graduation Day by the mayor himself. See, even nasty-little-trollism is going to get you eaten and Snyder's untimely death meant that he didn't get to see his beloved school blown to bits.