Brian ("Good Omens")
For Brian from A Hat Full of Sky see Brian ("A Hat Full of Sky"), for Brian the baron's guard see Brian Roberts
Brian is a member of the Them, the gang of children who join Adam Young in his various enterprises.
In person, Brian is plump and always dirty-looking, there's something "ground in" about the grime on his face, hands and knees that resists ordinary soap and water. Brian generally seems the most cynical and skeptical of the Them, expressing disbelief of the claims of Adam and Wensleydale. He is also, as befits a young boy, a little naive and literal-minded. For example, he "knows" that nuclear reactors blow up often because the picture of one in Wensleydale's "comic" was an exploded diagram.
In the final showdown, it is somehow entirely fitting that Brian should be the one who is tasked with facing down and temporarily destroying Pollution. If the Four Riders of the Apocalypse are anthropomorphic personifications, the condensed essence of thousands of years of human hopes, dreams, fears, nightmares and general experience, then it makes sense that Adam's three closest chums should each have something of the essence of one of the riders about them - and, being human, come out fully triumphant in the confrontation. Death is perfectly aware of this, which is why He concedes a draw with Adam.