Muten-Rôshi trained Grandpa Son Gohan, Ox King, Son Goku, Kuririn, and Yamcha.
Special thanks to to hold this voting poll to let Anime fans decide whom of all Anime characters are the most perverted men among them.
At least he still had the decency to keep it to female gendered humans.
However, in anime, it seems to have become a trend in recent years like some people were discussing the other day over here with titles like OreImo and Yosuga no Sora and the proliferation of Imouto routes on Date-sims.