Dinin Do'Urden was a drow fighter of House Do'Urden of Menzoberranzan. He later became a drider. Dinin was the son of Matron Mother Malice Do'Urden and house patron Rizzen Do'Urden. He was the brother of Drizzt Do'Urden, as well as Nalfein, Briza, Vierna, and Maya. In 1297 DR, secondboy Dinin accompanied the soldiers of House Do'Urden in a successful attack on House DeVir. During the battle, Dinin took advantage of an opportune moment to distract his older brother, Nalfein Do'Urden, and put a sword in his back. Dinin then ascended to become elderboy of House Do'Urden. That action fortuitously saved the life of newborn Drizzt Do'Urden, who was to be sacrificed to Lolth as the third living son; Nalfein's death was deemed an acceptable sacrifice instead.

Twenty years later, Dinin became a master at Melee-Magthere, the drow academy for fighters. He watched over his younger brother, Drizzt Do'Urden, and was a member of the same training patrol, along with Masoj Hun'ett and Berg'inyon Baenre. In one of their excursions into the Underdark, Dinin cut off both hands of the svirfneblin Belwar Dissengulp, sparing his life only after Drizzt convinced him that the gnome could return home as an example to those that cross the path of the drow.

Dinin was recalled to House Do'Urden when Drizzt graduated in order to add strength to the house's upcoming war with House Hun'ett. In 1339 DR, when House Do'Urden was destroyed by House Baenre he was spared by Jarlaxle under the conditions that he join the mercenary band Bregan D'aerthe. He became a trusted ally of Jarlaxle until he was turned into a drider by his sister Vierna Do'Urden for openly mistrusting his older sister's motives. In Vierna's personal attack on Drizzt Do'Urden in 1357 DR, the transformed Dinin was killed in a vicious battle with King Bruenor Battlehammer. Dinin was brought back from the Abyss by a handmaiden of Lolth as the torment of driders did not end with death. Dinin jumped into the remove curse web that Quenthel and Yvonnel Baenre had weaved with the birth magic of Catti-brie, restoring Dinin back to drow form, along with eight hundred others. He begin life anew in Menzoberranzan under the false name of Dininae. The restored former driders organized into a group known as the Blaspheme. Dinin grew close to it's leader, Mal'a'voselle Amvas Tol, and her lieutenant, Aleandra thanks to the fighting skills that he had learned under Zaknafein, though neither believed him to be a houseless rogue from the Stenchstreets as he claimed himself to be. While stationed in House Do'Urden though, Aleandra noticed that he seemed to be expertly familiar with the building's layout, which led her to discover his true identity. When Aleandra was captured by House Melarn, she used this knowledge to bargain herself out of being cursed back into drider form, and Dinin was soon captured and tortured by House Melarn. Dinin was forced to agree to get close enough to his estranged brother that he could murder Drizzt's daughter, Brie. Fearing his fate at the hands of Lolth herself should he abandon this charge, he resolved to do so, even after his escape from Menzoberranzan and return to working for Bregan D'aerthe