Adnan is an NPC who befriends the player during the anarchist questline. He actually gives the player the Taylors Revenge II quest that results in killing mayor stevens.
Adnan is the brother of the Immam. Not as religious as his brother and preferring to spend his days tinkering with cars, he nevertheless ultimately helps Immam attempt to get elected to replace mayor stevens and assists the player on the final set of quests on Fionas arc.
Adnan is killed by Fiona in the final quest of the game, dying attempting to help the player rescue his brother.
Adnan gives several sweet pieces of gear, including Adnans armor, the Remington Gauss shotgun and later he gives the player a submarine for the Taylors Revenge III quest.