Hi, I'm looking for a hentai I read back in 2007 or before that time. It was about a heroine with short hair and strong personality. She had a male companion who were fond of her, though she didn't like him at first. I remember the manga has several chapters.

In the first part, they encountered a girl who controlled a machine or so, and her boobs were huge, lol.
And there was a scene while she and her companion were having sex in a car in the desert, they got attacked by the demon lord's underlings (as I vaguely remember, she messed up some of his plans or sth). She got kidnapped and the dude was severely wounded. And obviously, she was taken to the demon's place, got raped by the demon lord.

That's all I could think of for now.So I would appreciate if you could help me find out the name of this manga. Thank you.