The curtsy lunge hits your glute medius—one of your glute muscles that helps pull your legs away from the midline of your body—and also strengthens your abductors (outer thigh) and adductors (inner thigh). I love fiinishing off with this on my leg day, you can play around with the angles, depth and reps to target different areas. I use a light barbell which helps me maintain stability but you can use heavier, just watch your form.
Quick tip: Start standing with your feet shoulder-width apart. Bring your left foot behind and across your body as you lunge downward. Both knees should be at about 90 degrees. Try to keep your front knee from going too far over your toes.