I never really wore bikinis to begin with. I mean, I'm a baker. I'm surrounded by cakes and cookies all day. I've never been a size 2. (Add 10 to that, and you're getting closer to my actual size.)
I've heard it does... I've honestly never tried it. What's Bio Oil made from?
So long as it doesn't get too hot. I like a bath around 90 degrees, and I think that's fine. If you're sweating, it's too hot.