Overview
Nog was born to Rom and Prinadora on Ferenginar in 2353. Later, he moved with his father to Deep Space Nine and worked at his uncle Quark's bar. During this time, Nog was very mischievous, and a slight delinquent. With new best friend Jake Sisko, he is, though reluctantly, one of the first students in Keiko O'Brien's school. When Rom, under pressure from Quark and Grand Nagus Zek, pulls Nog out of school, Jake tutors him behind Rom's back ("The Nagus").
Recognizing his father's failure to capitalize on his proficiency with mechanics and electronics, and not wanting to follow in those footsteps, Nog resolves to go into a career where he can make something of himself. After going through the Ferengi coming of age rite, he requests an apprenticeship under Commander, later Captain, Benjamin Sisko in order to attend Starfleet Academy ("Heart of Stone"). Nog is admitted and becomes the first Ferengi in Starfleet ("Facets").
Starfleet assigns Nog to Deep Space Nine as part of his cadet field training ("The Ascent"). Upon returning to the station, he becomes roommates with Jake although his newfound Academy discipline is initially at odds with Jake's slovenly habits. As a cadet, Nog works mainly under chief of operations Miles O'Brien.
Nog receives a commission as ensign shortly before Starfleet retakes Deep Space Nine during the Dominion War ("Favor the Bold").
In 2374, Nog is sent on a diplomatic mission to Ferenginar with Jake, who is along as a civilian press correspondent. They are rescued by the USS Valiant after their runabout is destroyed by the Dominion. On board the Valiant, Jake and Nog discover that the vessel, including all senior officers, is composed entirely of an elite group of Starfleet cadets, called Red Squad. Nog becomes enamored at the thought of working with such a group, and the young Captain soon gives Nog a temporary field promotion and officer position on the ship. An arrogant, overly zealous crew, they embark on a poorly-planned mission to seek out and destroy a very powerful Dominion battleship... based solely on an untested scientific hypothesis which states that a specific radiation emission could be used to cripple the Dominion ship's hull structure. Jake objects strongly to the recklessness of the endeavor, but is blatantly ignored and ridiculed by everyone, including Nog. Eventually, the Valiant encounters the Dominion ship, and the young crew become visibly shaken when they see how huge this particular enemy ship is, from the viewscreen. They make the first offensive strike on the enemy anyway, but quickly discover to their horror that the theory is flawed. The radiation has no effect, and the Dominion ship retaliates, resulting in the total destruction of the USS Valiant. Finding an escape-pod, Nog, Jake, and a female cadet whom Jake befriended earlier are the only survivors ("Valiant").
On AR-558, during a battle in the height of the Dominion war, Nog is shot in the leg by a Jem'Hadar soldier, necessitating its amputation ("The Siege of AR-558"). He then spends several months at Starbase 235 where a biosynthetic leg is grown for him to replace the amputated one. After months of therapy Nog still feels phantom pain in his new leg, even though the doctors couldn't detect any stimuli in its pain receptors. Nog chooses Vic Fontaine's holosuite club simulation as the place to recuperate from the trauma of war, to adjust to using an artificial limb, and to escape from his real life ("It's Only a Paper Moon"). This becomes a problem when Nog decides to live in the holosuite full time and refuses to leave. It is Vic himself that finally has to force Nog to leave by shutting down the program (an ability that Vic has since he is a sentient holosuite character.)
One of Sisko's final acts before joining the Prophets is to promote Nog to the rank of lieutenant junior grade (DS9: "What You Leave Behind").
In an alternate timeline, Nog becomes a Starfleet captain ("The Visitor").
In the Mirror Universe, Nog owns the bar on Terok Nor, having inherited it after the deaths of his father and uncle. The mirror Nog helps Intendant Kira Nerys escape from the Terran Rebellion; however, the Intendant subsequently executes Nog, fearing that he might tell the rebels where she is ("Shattered Mirror").
Nog is known to store his money in a locked box under his bed.
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