I don't know what was going on but (s)he was just sitting there, on eye level with the pedestrians, cawing and making other strange noises (like the velociraptors in Jurassic Park, if anyone remembers).
The Japanese crow is much bigger than the European carrion crow, with a feather beard like a raven and a powerful beak. They look pretty intimidating and make a mournful "kao! kao!" call.