The answer to this comes down to them just not feeling a sense of danger. Orra was warm and sweet pretty much from the get-go, minus thinking MC was some random schmuck trying to hump her. Once she realized it was an accident she scooped him up into a breast-smothering hug cause he was too cute for her to handle xD.They could just... not accept and if she tries anything, scream bloody murder? I'm happy that it ended up well but I'd not have done that honestly.
I come from a small-town background where people are just genuinely friendly. People say hello to you and give respect to each other. I've been stopped multiple times in the middle of the grocery store to just casually chat with someone I've never met in my life because they were just a friendly soul interested in meeting me and learning my story.
Orra didn't force them and was offering a kindness for delivering her letter back to her. They could've denied it and she would've instead just offered them directions to where they were going or to pay for their rental.
Crazy shit happens when people are kind to each other. All it takes is a gesture of kindness to change the world for the better.