Here are the links to the manga:
http://www.megaupload.com/?d=DLRLA0ZI (Ch.1-4)
http://www.megaupload.com/?d=6E0I5QK1 (Ch.5-8)
It looks as though the main character grows bigger breasts after having sex.
BTW Never mind the megaupload names as they are random names chosen for the files.
Once the RAR archives have been extracted, you will see that it's the manga folders.