She told me one time a girl kissed her at a house party when she was younger. I asked her if she enjoyed it and gave me a firm "no" (who knows, maybe she is lying and enjoyed it a little?). But if she isn't bi-curious or bi-sexual, is a threesome completely off the table? Or is it possible she still would consider it, if she is deep enough in my frame and would do it just to please me?

Also, if I mention it and she ends up getting turned off by the idea or thought of me wanting one, do I risk her getting upset with me (since we are in a "committed" relationship)? i.e. getting mad because I want to have sex with her and another chick. She does seem a little possessive in the sense that she probably wouldn't want to "share" me, so I feel like I have to tread carefully.

I've also heard that I have to make it seem like she thinks it is her idea...so how would I go about doing this? Or do you guys think that a possibility of threesome isn't going to happen with this chick?

For reference, she is very submissive, has high interest/attachment, sees me as the prize, told me she loves me ect. Been dating her for over a year now.