I actually just wrote an article on this for EVO and n2bm.com.
First, if your girlfriend is a genuine 11% body fat, that is incredible for a female.
Any steroid, even steroids with a high anabolic:androgenic ratio will still have androgenic side effects associated with them. Androgenic is a fancy word for maculating - hair growth, deepening of voice etc.
SARMS on the other hand are completely anabolic. There are no maculating side effects associated with them. I would look into the SARMS triple stack:
http://www.evolutionary.org/the-SARMS-triple-stack-protocol
For a female, use haft the dosages listed in the article.
- - - Updated - - -
SARMS would make her test positive on drug test by the World Anti Doping Agency standards. Yes.
She is definitely 11% bf, without a doubt. She has fantastic genetics, fast metabolism and she eats, sleeps and dreams about gains just like me. Thank god it is the off season and she can run this before any tests would be given. (even though there are no tests, just to be safe) Shes on board with the Osta and Gw not too into S4 but I'm gunna get her it anyway and make her use it lol