The Overflowing Bra

Nickname already said everything that I could've said.

The first chapter shows great promise, but the shape shifting tapers off to almost nothing thereafter. Personally, the idea of having even one woman who can change to suit her lover fascinates me.  Imagine having several competing!

The first part is the best. But your need to break out of the story and narrate is jarring and greatly detracts from the actual story.
And why did you break it up into 4 files anyway?

Liked the plot and very enjoyable at the start but I agree with Nickname's and Kanodin's main points, the plot seems to be going too quickly towards a dead end. I don't know if your intention was to write a BE story, but I feel there's not quite enough BE here. Personally, I would like a bit of pregnancy and/or big bellies thrown in too.
Nevertheless, good writing style, grammar and vocabulary so I am looking forward to the next installment.

I like where this is going!  Keep it up!

Interesting read.
I would hope an invasion of shape changeing  aliens would be 'nipped in the bud'.
They were unrealilisticly  quick  to gain citizenship in the story.
Nobody noticing the falling birth rate?
The shape-shifters aren't doing anything to breed replacement  humans.
We eat cows, and as long as there's a  McDonalds, they won't go extinct.
Looking forward to future installments.
Maybe some un-mutated males are getting similar treatment from human women.
(In their secret underground breeder lair.)

I haven't yet read it, but I'd be damned if the description doesn't sound exactly like XXXecil's "300 Million".

Abundant material to stroke to; writing demonstrates a strong command of compositional skill; typos are occasional but understandable; story leaves almost no hope for the characters involved. Rather sad, and I hope later installments are more positive.