Where does the reabsorbed fat go?

Fat transfers are increasingly popular ways to improve the shape and size of one's buttocks and breasts. When we do this procedure, about 50-60% of the transferred fat will achieve an adequate new blood supply to become a permanent fixture to the new site. The remaining fat cells will be broken down by the body and excreted in your waste. It will not set up residence elsewhere in your body.

Hi. Fat cells just get reabsorbed by the body and excrete, thats all.
Depending on the technique use to harvest the fat,  adyposites cells may remain in good condition for transfering and survival  one in  the receptor area. Being the traditional Lipo the best for this purpose.
Still breast implants have  no  substitute for Breast Augmentation. Is the safest and aproven way to do it.
International Member of the American Society of Plastic Surgeon
Member of the International Society of Aesthetic Plastic Surgery

Fat grafting to the buttocks and breasts are becoming more popular. Approximately 40% of the fat grafted does not survive for a number of reasons. The fat that does not make it is broken down into multiple organic products including calcium formation. Most of the broken down fat is excreted through our kidneys after having been processed by the liver. Fat does not get “absorbed” and reappear in other areas of the body. 

That is an excellent question. The fat will be re-absorbed by the lymphatic system and digested by your immune cells and then processed by the liver and kidney and excreted from your body. The fat cells won’t leave from your breast and travel to another part of the body or return home from where they were suctioned.
The fat cells don’t leave intact—there is not 100% take of all of the fat because some of the fat cannot establish a new blood supply so they are not intact to travel.