PPPD-911 Her older sister has big tits and is okay with in-the-vagina sex, and she's seducing me

My girlfriend absolutely won't let me do it raw! Helplessly, I put on a condom and have blindfold sex with her, but then her sister comes in and flaunts her huge tits to tempt me! Even though I'm fucking my girlfriend, there are these massive tits right in front of me... and she's even okay with doing it raw, making it even more tempting! I do love my girlfriend, but how can I resist such a beautiful and sexy woman? The thrill of possibly getting caught by my girlfriend and the excitement of having sex without a condom sends my arousal to the max... In the end, I explode inside her right in front of my girlfriend!