If you have any fat on your legs, doing glute workouts will only tone them and make you lose the fat. They won't get bigger. They will tone and become muscular.
Focus on one or the other. Maybe focus on losing fat off your thighs first, then when you reach your desired level of leanness, start a program focussed on adding muscle to your glutes. It is very hard to lose fat AND build muscle at the same time.
True!!! Just dont skip a workout ever!!