Sleepy is one of the buttons on the Arhu SparkMaster 5000 Universal Controller in Divinity: Original Sin
Press sleepy in the right combination of Arhu SparkMaster 5000 go into one of the following modes:
Sleepy - Sleepy - Happy: WEAPONS DEACTIVATION MODE!
Angry - Angry - Sleepy: SELF DESTRUCT MODE!
See below for more info: