Gokudera would likely have yelled, kicked, and thrown dynamite at Damian if he'd actually been caught with his hand down his swim shorts for embarrassing reasons. Hiding weapons is usually something he has a lot of experience doing, and he already has a few sticks on him that aren't visible.

He scoffs at that careful kick and glares before shaking his head. Honestly, neither, but if he had actually been planning to use his dynamite, it'd be in protest. He wouldn't want to injure anyone, no matter how innocent they may or may not be. Ruining the party doesn't have to mean causing injuries, though it's not outrageous to assume that.

"Why does it matter to you?"