MC: "Hey, I know you were just nearly raped and I'm a complete stranger, but lemme shove my hand in your throat with the only warning being a request to open your mouth. While i'm at it I'm also going to need you to trust me, the stranger you just met after nearly being raped, that this is 100% for your own good."
Heroine: "Of course! Also, not only am I going to have no problems with that situation, I'm also gonna go ahead and get horny from it because why not? This is an isekai power fantasy manga so of course everything MC-kun does is gonna turn me, the template big boobed hot girl, into a fire hose."
A+ writing.