A sick man invited a magician to his house to cure him. After examining the man, the magician told him that the sickness has no cure but the only way out is to transfer it to another person.
The man obliged and asked "how?"
The first person to enter your room, shout "kai" and the sicknes will be transfered to the person. The man thanked the magician. The magician left. The sick man left his door open waiting for the first victim to enter his room. when the magician was on his way home, he remember that he did not collect his money for the service he rendered. He decided to go back to collect it. When he got to the man's house and entered his room. The man shouted "kai". The magician shouted back "rekai". The man shouted again "rerekai". The magician shouted back "rererekai".
Till now they are still shouting