User blog comment:Omega natsu2/Episode 181: Fairy Tail vs. Executioners, Review./@comment-24277053-20140510030854/@comment-7418318-20140510074035

If you drag your eyes away from Lucy's boobs for a moment, you might notice that Natsu is covered in paper slips that make it impossible for him to move. If it's impossible to move, it's also impossible to intentionally gab her boobs.

To me it looks like he was in the process of either shielding Lucy with his body, or pushing her aside so she won't get hit when he was paralyzed.

But that makes it into an even better NaLu moment than some random boob-grabbing ever could.