Do Not Sit On Pillow Or You Will Get Boil On Your Butt. The (headrest) pillows which are commonly used when we sleep. According to Javanese custom it is inappropriate to sit on then with your buttocks. Since they are children, the Javanese people are taught to treat the head pillows appropriately. It is a taboo to sit on it. To make their kids obey the rule, the parents simply warn them that if they dare to break it or sit on it they will get boil on their ass. The myth is so entrenched and sometimes adults subconsciously believe it is so.