It’s called rib flare, very common with people who sucked their tummies in growing up. If it really bothers you, you can find certain workouts that are supposed to help you target that area and help you. Or breathing may be the culprit. I was overweight growing up, I’m (20f) 150 now and still have them. Most of the big names in fitness recommend ab workouts that target the lower stomach because the lower abs are much harder to achieve than upper abs. (ie. if you can see your lower abs, cont.