How's this for a start - you all have gotten to know one another over the last few years, maybe met in school, at work, whatever. You started out as poker buddies, then hunting and fishing buddies. At some point you'd happened across a lone female hiker who wanted to have sex with you.
You liked it so much that you started looking for girls who wanted to, and when you couldn't find one, raped one. And that was so much a turn-on you stopped looking for ones who wanted it, just took whoever was available, whether she wanted it or not - preferring ones who didn't want it LOL.
Y'all can work out details if you want.