I'm not sure what the purpose of a drain would be in a Brazilian butt lift done properly. The fat is placed with small cannulas 3mm or less into the gluteus maximus muscle, deep fat and superficial fat in small amounts of 2mm strips upon withdrawing of the cannula. If a large amount of fat is placed in one place, this will end up liquefying and might need to be drained. Proper surgical technique avoids this. Some doctors use drains in the areas liposuctioned to collect the fat for transfer to the buttocks. See a board certified plastic surgeon with experience in advanced body sculpting techniques for an in person consultation/evaluation. Good luck.