Couples gets on more guy to joined

Interracial sex type of girl who is a conservative outside but very wild in terms of thinking, why? because she is always thinking to have sex with another guy. There was a time that she can’t take it anymore and she just tell her boyfriend that she want to have sex with another man. Her boyfriend responded and saying that it was cool but they must settle a rules first. Her boyfriend is fine with her interracial sex girlfriend idea but there is one thing her boyfriend demands for. It has to be done when he also joined their intercourse.