As the Courier meanders around the settlement of Goodsprings, and hasn't met Mr. House at the Lucky 38, one may spot securitronVictor zipping around on its single tire. The Courier can thank him for the rescue from a shallow grave, ask what he's doing, ask about the men who jumped them, or tell him to stay out of their way.
Once in Novac, the Courier begins to feel a bit suspicious towards Victor when he turns up for the second time on their way to New Vegas.
Continuing on the way to New Vegas, the Courier can stop by settlement Boulder City. Currently, it's occupied with NCR troops and a group of Great Khans, but it's not only them; old pal Victor has also decided to pay it a visit.
Entering the New Vegas Strip for the first time, the Courier is greeted by Victor one last time and will tell that his boss (Mr. House) wishes to speak with the Courier in the Lucky 38.
After the conversation Victor will stay in the Lucky 38 or outside it. It appears to be 2 different securitrons that switch to Victor once inside and outside the Lucky 38. Similar to the securitron outside Victor's shack.
It is possible to talk to the Victor right in front of the door to the Lucky 38 before talking to Victor on the street. The Victor on the street will talk to you directly after, which can even be confusing to some players who have played through the game several times.