Little is known about Jeannie May's background. It can be uncovered that she met with a slaver working for Caesar's Legion and sold Carla Boone, the wife of former NCR sniper Craig Boone, into slavery. Craig Boone reveals that the slavers knew how to approach Novac without being seen, which suggests that Jeannie May gave them detailed instructions on how to get in and out safely. She was paid 1,000 caps for Carla, and 500 more for her unborn child. Jeannie May possibly sold Carla because of the way she acted. Through dialogue with Jeannie May and other residents of Novac, specifically Manny Vargas, it is revealed that Carla was not well liked, and "went out of her way to be rude." In actuality, she just wanted to get Boone to take her back to New Vegas, which she personally preferred over the quiet and uneventful life of Novac, and apparently didn't care whether or not her favorable interests made plenty of others see her as selfish.
One for My Baby: It is revealed that Jeannie May sold Boone's wife Carla and her unborn child into slavery to Caesar's Legion. After the player leads her to her death at the hands of Boone, it is possible to loot her body for a key and use it to unlock a safe in the room at the entrance. Unlocking said safe will make the player able to get a note (bill of sale), incriminating Jeannie May of selling Carla into slavery.
The player can purchase a hotel room key from Jeannie May for 100 caps, or for free if the player has Accepted status with Novac. She stipulates that you can use it "until the busy season comes," which translates to "indefinitely."
If asked about places to shop, she will direct the player to the souvenir shop. If you mention it to Cliff Briscoe, he will then offer a discount, and with sufficiently high Barter and Novac reputation, will sell and buy at base cost.
Should the Courier kill her, as opposed to allowing Boone to shoot her, the Courier will be rewarded with good Karma, but bad reputation with Novac. Taking this course of action will make it impossible to complete One for My Baby.
She narrates the ending slideshow for Novac.
The following is based on unverified behind the scenes information and has not been confirmed by canon sources.
She seems to be named after the main character of famous novel "Their Eyes Were Watching God", Janie May Crawford.
"Well, saints alive. That is a load off. Nothing to be done, though. Those ghouls just didn't know when they weren't wanted. Couldn't take a hint. And aren't you just the most unexpected gift our little town ever had? Here, take this. And go buy yourself something nice."
"Nothing that wouldn't be wrong with any man who loses a wife, I suppose. Poor dear. I know he thinks she was kidnapped, but I'm not so sure she didn't just run off on her own. You could tell she was thinking about it ever since they arrived."
pcps3xbox360 If you don't ask Jeannie May to come out to the front of the dinosaur when you first talk to her about Boone's wife, the dialogue option won't appear again later. To lead her there after that, you must go to her house at night and wake her up. When you talk to her then, it will give the option again. [verified]
pcps3 After revealing her past and allowing Boone to deal with her, all the items in her house will inexplicably be marked red. However, stealing them results in no Karma loss. Her fridge lock (Average and red highlighted) can be picked for (base) 44 XP and no Karma loss. Her bed still can't be used though. (Note: Her house can reach this state before you kill her and as long as you've picked up the Bill of Sale as well) [verified]
pc Sometimes when going to her house to tell her to accompany you out in front of the dinosaur, if you push past her to exit the front door as she is exiting, she will freeze just outside her front door. Waiting will not help and the dialog option for her to follow you is gone. The best 2 options is load from a previous save (autosave will not help) or "push" her all the way in front of the dinosaur. To push her just get behind her and walk forward keeping the mouse centered on her at all times or you will slip past, this is a bit tedious but it does work. [verified]