Цукабіші Тессай

He is known to buy TV-displayed medicines, which do not always work or have unpleasant side affects, much to Urahara's chagrin. He is also among the few who find Orihime's strange food ideas tasty, the other being Rangiku Matsumoto. Tessai is a large, muscular dark-skinned man wearing square-shaped glasses and with an enormous handle-bar mustache. He is always seen in a white shirt with a blue apron, although during his time in soul society he wore an ornate dark robe over standard shinigami garb. In the past, Tessai was once the leader of the Kidō Corps in Soul Society. The reason of his exile to the Human World is for using a forbidden spell even though it was for an unsuccessful attempt to capture Aizen.

Currently he works as Urahara's personal assistant in both business and other duties. He has apparently held a position among the Shinigami for quite some time, at least 200 years, since he informed Rukia Kuchiki that the word "Quincy" "brings back memories" from that long ago. Source: Blech Wiki