If people read the story you could see she was a virgin lol people skip and then are asking questions that was already answer lol
Yeah, it gets explained right in chapter 1 while it is being demonstrated that penetration is not necessary to resolve the effect of the collar (something that is also demonstrated every time after that), she just can't do it by herself but she's fine as long as someone else gets her off. Though, chapter 1 happens to be missing on here for some reason, and Shinsei doesn't seem to have a site anymore after their old site got hijacked.