My boyfriend is constantly spreading my cheeks while I'm watching TV

I'm just 18 and my boyfriend has a thing for my butt. He's always spreading my cheeks while I'm watching TV. I don't mind, it's kinda hot. He's always playing with my pussy and asshole. I'm not even wearing any panties and he can see everything. My friend came over and he saw my boyfriend playing with my butt. My friend got turned on and he started touching my boobs. I didn't mind, I was getting turned on too. My boyfriend took his dick out and my friend started sucking it. My boyfriend was fucking me from behind while my friend was sucking his dick. It was the best sex I ever had.