Me and my Boyfriend have been together for 5 years, and about a year ago, we got into polyamory. We had a girlfriend for 5 months, but she left us, and now we kinda want another one. There is this girl we like, but she just got out of a bad relationship. We knew her when she was with her Boyfriend, and they would come over and hang out. She would sit on my lap or sit close to my boyfriend. Now that she's single she wants to hang out. How should I ask her about being in a relationship with us.