Nova was born in 2252. At the age of 25, she spends most of her time hanging around the bar talking to the male clientele. Every now and then, she'll go up to a room with a new "friend." Her real job is to sweet-talk the male patrons and get them to spend money - on booze, company, or an outrageously priced bed for the night. One day a week -her day off- she goes shopping.
It's implied that she's lived in Megaton about 5 years starting at twenty years old. She eventually made the mistake of borrowing money from Moriarty and has been filling the role of courtesan to pay him off ever since.
Nova works at Moriarty's saloon as a prostitute to pay back the debt she owes Colin Moriarty. She hangs around the Saloon's first floor talking to the locals and the Lone Wanderer. For 120 caps you can rent a room with her.
If Moriarty is killed, Nova announces that she has quit her service and will find a better job. She is implied to have taken over Gob's job as she still hangs out inside the Pub, and sleeps there as well. If you pay for a room for the night at Moriarty's saloon after his death, Nova will still be in your bed when you wake up, despite having "quit."
Following in His Footsteps: After inquiring about Moriarty and completing a successful Speech check, she will give you the password for Colin's terminal, which contains valuable information about your Father. A male player with the Lady KillerPerk can acquire the password as well.
When you inquire about hiring Nova's services, she advises you to rent a room. When you inquire about the cost of the room, she replies, "Well... for you? A room and some company will run you 120 caps. Up front." After paying for the room, she directs you to the room with the "big bed," and straight after finishing your conversation, she walks up the stairs to the room, lies down on the bed, and appears to fall asleep. Attempting to speak with her at this point will result in the usual dialogue choices. However, you do gain access to the bed for a period of time after this.
Nova is not picky; both male and female players can acquire her services. If the Lone Wanderer is male and possesses the Lady Killer perk, the dialogue and innuendo from her becomes more evidently playful and suggestive. Some of Nova's dialogue, and comments from other Megaton dwellers, suggests she may have considered leaving the job and trying to move on with her life even though she supposedly owes Moriarty some caps, but no quest or dialog options exist to try and convince her to do this beyond a single mention.
"With Gob? Well, he's sweet... and I know he'd like to, it's just... well... I don't want to sound shallow or anything, I mean, I'm a whore, my standards aren't exactly high. But there are places even I won't go. Johnnies that are squishier than me are one of 'em."