Slap!
"Ouch!"
"Please, don't touch me. I don't like being touched by strangers."
As soon as Myne grabbed Fenrir's arm, she was as if struck by lightning, stunned in her place. After Myne finished speaking, she came back to her senses, and slapped him hard on the back of his hand, freeing her arm from him before quickly backing off with a vigilant expression.
It wasn't that Fenrir was overreacting or was too unsure of her role that she forgot Myne wasn't a stranger, but the other party's past deeds were too egregious, and she didn't want to take any risks.
God knows if he had some kind of mysterious way to get all women he lay eyes on, soon roll with him on the bed. At least before meeting Myne, she had never seen a person who not only had a dozen or more girls around him with whom he had genuine relationships but still dared to go out to find more, and his girls didn't say anything to him.