Leske is a casteless dwarf who lives in Dust Town along with all of the other casteless dwarves, as well as the player character if they chose Dwarf Commoner for their origin story. He works for the Dwarven Cartel and will eventually be encountered in Orzammar no matter what origin story is selected. Leske is a Rogue fighter and specializes in dual wielding. He comes across as being confident, but with enough acceptance to know his place within the structure of Orzammar and prefers to avoid confrontation. Leske also often cracks jokes and generally comes across as being laid back.
Dwarf Commoner Origin
If the player chooses the Dwarf Commoner origin, they will quickly be introduced to Leske who is shown to be a long-time friend of the player. He is also, quite literally, the player's partner in-crime; both the player character and Leske work within the Cartel as lowly thugs who do the bidding of the Cartel leader, Berat. He first orders the two to assassinate a lyrium smuggler, though it's up to the player if they actually kill him or not. Whether the player lets him go or not, Berat gives the player another job to help rig the upcoming Proving (arena combat) matches by slipping a drug into the opposing fighter's refreshments to make him groggy and less resilient.
The player and Leske manage to sneak their way into the Proving Grounds lobby under the guise of cleaners. Unfortunately before they drug the opposing fighter they find that Berat's own backed fighter, Everd, to be passed out. The player character then opts to wear his armor and fight in the Proving. The option to poison the player's opponent is still available should they desire, however.
No matter which is selected, the player character bests all of the competition. Though nearing the end, the real Everd stumbles into the ring, drunk and barely able to stand up, causing an outrage when the player is forced to remove his/her helmet. The player, along with Leske, is attacked and found waking up in the jail cells of the Carter. Berat had bribed the guards to allow him to take hold of the prisoners, and was planning to kill them so the trail wouldn't lead back to him.
Leske and the player character manage to escape, fighting their way past many Cartel guards and eventually Berat himself. Reaching the commoner quarter, they're greeted by a series of Orzammar Guards who also plan to kill them for defiling the traditions of the Proving Grounds. Their attempts are halted, however, by the Grey Warden Duncan, who through witnessing the player character's combat prowess and determination, conscripts him/her into the Wardens. Leske is also pardoned since he was at least instrumental into putting an end to Berat's Cartel.
The return to Orzammar as a Warden
When the Dwarf Commoner Warden returns to Orzammar, s/he is greeted by Leske with open arms who warns him/her of Berat's first Lieutenant, Jarvia, who has taken over the Cartel. Leske himself appears as if he hasn't made any progress within his life, though when he lures the player into a Cartel ambush, it is revealed that he is in fact working under Jarvia, stating that it was his only choice to survive.
As the Warden fights through Jarvia's troops amidst the underground, as a favor for Prince Bhelen/Lord Harrowmont, s/he will also have to eventually fight Leske alongside Jarvia, killing them both.
If the Warden character is of a different origin, Leske will instead be encountered in the jail cell barely clinging to life. He explains that he and his friend have been left for weeks, ''all for a stupid bet''. This implies that Leske and the Dwarf Commoner origin character still undertook the Proving Grounds fix, but in this reality weren't able to escape from their cells. The player can release Leske from his cell, which results in Leske giving the player his thanks and running off.