Sister Asks Me to Help Her Use a Butt Plug Before Her Big Race

So I have this big race coming up and I hear the weirdest rumor that using a butt plug will calm my nerves. I've never put anything up there before so I explained everything to my stepbro which I know is weird. It was kind of hot to tell him something like that but what happened next I couldn't believe because he actually helped me put it in and I felt so vulnerable and turned on at the same time.