Who is Lance Corporal Detritus from Men at Arms: A Novel of Discworld and what is their importance?

Lance-Corporal Detritus is the first troll to be admitted into the city watch, as a part of an equal-opportunities drive by the Patrician. Detritus at first encounters stereotyping and abuse from other Watch members and civilian's alike, for being a troll and for his famous slow intellect, but through his loyalty and bravery he earns the respect of Cuddy the dwarf and becomes instrumental in healing some of the rifts between the Troll community and the wider community of the city at large.