This is self-defense, but taught to you by MMA girls. If there wasn't a video and any caption to these pictures below, it would look a tad too sexy. Check out their advice below:

To start the head and arm triangle hold, you need to be on top.

And then you need to put your arm under your opponent's neck.

When you get a lock, you need to close your elbows and move your knees like below:

To get your opponent to tap out, here's the final move:

Check it out in the video below: