What happens after finding the 7 sages in Pokemon black?
you do nothing
he only is in Pokemon platinum and Pokemon black and white in Pokemon platinum you see him in jubilife city, and I think maybe at Team Galactic HQ. in Pokemon black and white after you beat the elite four, he is looking for the seven sages. after you find all seven sages he'll talk to you and he'll arrest the 7 sages. you will never see him again after that.