Well, the good news is that muscle weighs more than fat. Or, rather, a pounds of muscle is more condensed/takes up less space than a pound of fat. So while you will gain mass by adding ~20 lbs (sorry, dirty American here, I had to convert), it won't be as observable as gaining 20 lbs of fat. Plus depending on what kinds of workouts you do, you'll be gaining mass in differing places than you would fat.
...which I realize doesn't answer your question all that well except to say that I wouldn't worry about losing your figure all that much. Shirts will fit differently as you bulk up, so you may need to go up a size in those, but other than that you would still be about the same. The only advice advice I have is to looking into eating more protein heavy things rather than just your caloric intake.
Re: Off-Topic Thread
(Anonymous) 2018-01-30 04:29 pm (UTC)(link)...which I realize doesn't answer your question all that well except to say that I wouldn't worry about losing your figure all that much. Shirts will fit differently as you bulk up, so you may need to go up a size in those, but other than that you would still be about the same. The only advice advice I have is to looking into eating more protein heavy things rather than just your caloric intake.