Asked about an open relationship

My girlfriend of seven years recently asked me what I thought about an open relationship. She said she had always considered herself bisexual since even before she slept with her sister’s roommate in college.

She also admitted when we have sex, she sometimes thinks of a woman I side her.

I didn’t know what to say, but she said it was mainly to fuck other women. I asked if there was anyone in mind and she mentioned a girl at our gym who looks good and always showing off her body. I told her to explore that part of herself and she started dressing just as revealing to the gym and started texting with the girl. She did say she made the first move and made out with her a little, and she thought she could have gone much further.

I finally admitted I wanted to fuck her yoga instructor sister ever since I saw her panties through her thin yoga pants. She didn’t seem angry and said monogamy isn’t for everyone.

Now she’s wondering if it would be better to go home with her or take her to our house if that wasn’t too uncomfortable for me. If the gym girl was even into it, she suggested a threesome. I’m not sure how all this happened so fast, but her IG has more sexy women on the feed.