Yes Man

 is a securitron robot that serves as Benny's assistant in 2281. As part of the Wild Card: Change in management quest, you can upload 's data onto Mr House's computer after you kill Mr House, which leads to many new quest opportunities.

Background
Yes Man was originally a generic securitron robot working for Mr. House, like all the other securitrons found on The Strip. He was damaged by a pulse grenade, and was recovered by Benny. Benny then allowed a member of the Followers of the Apocalypse to examine the securitron, in exchange for repairing and programming.

Other interactions
After speaking to Mr. House, the Wild Card series of quests will begin. From this point onwards, the Courier will be able to go up to Benny's penthouse in The Tops Casino. There he will find Yes Man. Yes Man will explain what Benny's plan was; to dispose of Mr. House and plant Yes Man's A.I. in the Lucky 38 mainframe. The player can then choose to continue Benny's plans, and start the Wild Card: Change in Management quest. If you have killed Benny, Yes Man may appear outside the tops casino, near the entrance. If the courier tries to kill Yes Man, he will not turn hostile or flee, nor will any securitrons or civilians react to the courier. Yes Man will die, yet any quests given by him will not be failed. Returning to the same section of the strip, Yes Man will be back in front of The Tops, explaining that part of him is in every securitron and if one body is killed, his A.I. can move to another.

Should the player complete the wild card quest, Yes Man will take Mr. House's place in the Lucky 38. After the assault of Hoover Dam Yes Man informs you that he found pieces of code within Mr. House's mainframe that, in his words, "changes my personality" and says he will look offline for a little while until his personality change is complete (he never actually shows his changed personality due to the game ending). However, Yes Man clearly states that he's going to be more "assertive", basically stating that he will no longer be under your control, and possibly alluding to Yes Man taking over control of the New Vegas Strip.

Appearances
Yes Man appears in Fallout: New Vegas.

Behind the Scenes
In English slang, a "yes man" is an obsequious and unquestioning assistant or underling.