I'm always confused as to why people would only use anabolic steroids to get lean without using it first to get massive. I like to call this negative gearing
The whole purpose of using anabolic steroids is to obtain a new level of muscle mass that cannot be obtained naturally. Your not going to do this well if your eating below maintenance calories and trying to achieve very low body fat levels.
Smashing down a stupid amount of calories and dirty calories is not usually the best idea either. However, since you're naturally a skinny guy, you may not have a choice but to smash down some dirty calories to meet your energy requirements.