Nothing if you dont work out.
After you roid up, you need a PCT to avoid the flood of estrogen that is going to try to counterbalance the increased testosterone. Also, when you roid up, you're eating a lot more and once you develop that habit, it will likely continue which will result in extra weight gain. Look at Arnold, Hulk, any of those guys that did roids...
You will gain muscle and mass much easier but with your poor habits you will crash so bad after your cycle