Carrot Ironsfoundersson, better known as Captain Carrot of the City Watch, is the rightful heir to the throne of Ankh-Morpork. As such, he has the requisite birthmark, fresh-scrubbed good looks, and a really old sword. He also has charisma by the bucketload. He can convince street thugs to put down their weapons and play football. Just by being around him, you can't help doing what he wants - he assumes that everyone else is basically a decent person and they somehow can't help living up to his expectations.
Carrot was raised by dwarfs, and as such, even though he's six feet tall, he thinks of himself as a dwarf. Like all dwarves, he has almost no sense of humor and is distressingly literal-minded.
Carrot gets his name, oddly enough, not from his bright orange-red hair, but from his shape - broad shoulders and a tapering but very well-muscled body. His muscles have muscles.
Oddly enough, he gets along rather well with Lord Vetinari, perhaps because the two men share a passionate concern for Ankh-Morpork. Or maybe it's just his charisma.