I agree taking a plastic toy into your ass inserted from a woman does not make you bi, however, the truth is not that black and white. I do think it actually puts you down that path of starting to consider a real penis, and later you might act on it.
For me, it was 20 years from when I was first anally penetrated (by myself) to when I first even had a thought about real penis. Now I am definitely curious. Not really bi though I think. I am more into cock, but not men as a whole. There is another thread somewhere exploring this subtle detail.
One thing I am sure of is that it doesn't make you gay. If anything (this is important), your lust for women will grow in parallel with your new lust for men.
