She heads left towards the Pens

Moving quickly, Supergirl walks along the dim hallway heading in the direction marked "Pens".
'Huh, whatever is flowing through those pipes sounds a lot more fluid than what came from the other side, I wonder what- ah, there's a door... no two!'

At each side of the end of the hallway there is a door, on one side is a steel door marked "Fertility" with a keypad next to it, on the other side is a more normal looking door with "Dairy" across it.

'Huh, I guess they really make their White Russian fresh here, maybe if I can... shoot, lead again, can't see.'
Focusing her hearing, she can hear what sounds like a lot of sucking sounds with the occasional lowing.
'I guess these are milk pipes or something, I should check inside to be sure before exploring the other directions'

As she opens the unlocked door and sneaks in, she sees what seems to be a small one person office, with a door on the other side marked "Milking pens"

'Ok, not what I expected from that sign, hmm, what are these pamphlets... oh... that's a lot of big boobs'

Looking at the first few pamphlets they are all the same one, showing a group of very well endowed women smiling at the camera.
The text itself promises an all natural breast enlargement routine where you get paid instead of paying, touting the expertise of professor Nina Dowd.
'That sounds like a scam, and Dowd... Dowd... didn't the Titans say something about sending her to jail or something? I distinctly remember Jason saying she was mightily endowed or somesuch'

Digging further down in the pile she finds a few advertising for women who want to live out their fetish and get paid while doing it, with pictures of a smiling woman attached to a milk machine.
'Huh, people have the weirdest fetishes... I wonder how it would feel to be her... no responsibilities, no worries, just eat and exist... that actually sounds kinda nice...' With a small smile on her face Supergirl looks lost in thought for a few moments before she snaps out of it.

Putting the pamphlet back where she found it she looks around with her x-ray vision and notices some different papers in one of the desk drawers.
Hurrying around and pulling it out, she finds some distinctly more questionable material, advertising to husbands and boyfriends that they can get a monthly recruitment bonus if they deliver their women here, and once the women return, they'll be much more busty as well as more accommodating.
'That doesn't sound good, I wonder if any of the missing women have been caught up in that... only one way to find out'

Walking over to the door at the other side of the little office, Supergirl opens it and steps half way through before freezing in her track.
On the other side is what looks like the inside of a surprisingly large barn, with row upon row of pens each containing a naked woman on her hands and knees.
All of the women have what seem to be milking machines on their, mostly, well endowed breasts, attaching them to a network of pipes and fully half of them are also visibly pregnant.

'Oh Rao, that's... that's something else... are all of these here for the breast enlargement, or is it the fetish thing... they do all seem happy and content... and curiously incurious... I should-'
"Who are you, and what are you doing here? I wasn't told of any additional intake." an older man in denim overalls is hurrying towards her, as he gets closer he stops suddenly as his eyes widen "Oh... you're... wait are you her? I did see a bunch of costumed customers arriving as I got here"