Is this already FORBIDDEN? Sex with your ex-boyfriend!

Today after partying I was so horny... that I no longer had control over myself. When I got into the car I was so horny that I actually stopped at my ex's house for a hot fuck. Since I still had his apartment key... I just went through with my plan mercilessly and unlocked his apartment door and let him straight in hot lingerie welcomes you! How did he react to my spontaneous visit? How would you react to that?