[Luckily, Sasuke has been doing this a very, very long time. He waits for Senri to punch, and he hardens the muscles of his abs. The best place to practice is the stomach for this reason. When Senri hits, they're solid and almost immovable.

Looks like they aren't just for show.]

Again. You aren't going to be punching him in the stomach. If you want to punch in the chest, you hit here. [He lifts his fingers to brush his sternum at the apex of where the shirt hands open.] Otherwise, it's better to hit the neck, if you can.

Since you just want to punch him rather than hurt him, just aim for the cheek. [A pause.] Does he know how to fight?