Did you know in Yakuza 1 during the sub story Drain The Lizard (English)/The Man In The Toilet (Japan) in Chapter 6 you meet a man who’s looking for some toilet paper. Give him some tissues and he’ll reveal himself to be Gouji Rokkaku from Jet Set Radio!

His first name was mistranslated in the English release but there he is! 

Does this mean Yakuza and Jet Set Radio are set in the same universe?!

There are of course the Benten-cho arches to remember...