Karin charges and slaps her opponent with a explosive tag. The force of the slap knocks the opponent across the field, and the explosive tag detonates after the opponent hits the ground.
This technique's name might be a pun on "tsundere".
When this technique is used on Sasuke Uchiha, the animation changes. The explosive tag detonates in the air, and when Sasuke falls to the ground, Karin runs over to the injured Sasuke and fawns over him before hastily jumping back.