Tsunade usually only teaches chakra control to older, lower-ranked ninjas. But one day, Naruto was exhausted from his training with Jiraiya and asked Tsunade for help in recovering his energy. All he had to do was pull down his pants and Tsunade would apply the handjob technique (another ancient technique, learned from the old prostitutes of Konoha). Tsunade concentrated all her chakra in the palm of her hand, keeping it sloppy and wet, in order to get a long cumshot out of Naruto balls.