She's ready to have his babies now.I have a feeling he just awakened something in her. Now that she knows he'll hit her she's gonna be waaaaay more interested in him.
I assumed it was dark and she was on guard regardless of her vision. Him fumbling with the keys instead misled herAlso, if she really was just standing still with her eyes closed for 3 seconds like the manga seems to be suggesting then why did MC wait ntil she opened her eyes to punch her in the face? Punching her in the face would have been ecen more effective when her eyes were still closed since a punch you don't see coming is much more disorientating.