The main reason to stretch your inner thighs and groin region is release tension in your lower body and to increase flexibility and strength in this area. There are several ways to stretch your groin region and this is a simple version you can do when sitting on a chair or at home in the couch.
Sit on the edge of a chair. Spread your legs wide apart and with your toes pointing out. Tense your abs and lean forward with your elbows on your knees. Gently apply pressure to push your thighs apart until you feel tension in the groin area. Hold the position for the desired amount of time and then repeat.