We made a habit of it when she was babysitting me.
Eventually we got naked and found out how and we screwed.
I did not want it, but he insisted and I gave in.
In actual fact I've done similar with my Step-Sister when she was really drunk and I sort of had to carry her home and lift her and put her to bed - she was not in a good state luckily I hadn't drank vary much anyway.
I am sorry to hear of you being in this situation that you were molested by your brother and then he insisted on having a sexual relationship with you.
We live together now and some people question but we dont care mostly.