What paint is best to use when painting people's skin?

I%26#039;m doing an art project and want to paint the human body but i%26#039;m not sure what paints to use. All I want to do is paint the person, take some photos then they can wash it off.|||try poster paint. It%26#039;s cheap and way thicker than watercolor paint plus it%26#039;s very practical.|||I would use my semen