Board Thread:Questions and Answers/@comment-13429037-20130726043727/@comment-10587310-20130726051116

Kisuke Urahara and Tessai Tsukabishi are normal Shinigami which are souls with exceptional spiritual energy. Who have been trained to control and wield their spiritual energy. The Vizards are Shinigami that have undergone Hollowfication and gained the powers of Hollows on top of their Shinigami powers. The reason they can be seen by normal humans without spirit powers is because they are wearing Special Gigi's created by Kisuke. Ururu Tsumugiya and Jinta Hanakari are humans that work for Kisuke.