Name: Okuda Takiko
Pronunciation: oh-ku-da ta-key-ko

Takiko was Priestess of Genbu two hundred years before Miaka and Yui's time.

***SPOILER WARNING*** (for tv ep.42?)
When Takiko called Genbu, she merged with him so as to be able to use his powers. After using the three wishes, she was returned to Japan, dying and in much pain. Not wanting to see his daughter in so much pain, Takiko's father, Okuda Einosuke tranlator of the ShiJinTenChiSho, killed her to give her peace. It was this "crime of love" that Keisuke and Tetsuya found in the library to lead them to Oosugi Suzuno.

Star Pattern: Aquarius
Seishi Name: Urumiya
Pronunciation: u-room-ya
Character: Roof top

As close as i can tell, it was Urumiya who was with Hatsui in the OVA1 #2&3. if so, Urumiya had white hair and was a boy. {thanks to Gail for capturing this pic for me.

Hatsui was shown with who i think is Urumiya in the OVA series. Hatsui is a boy with dark brown hair.

Star Pattern: Pegasus
Seishi Name : Namame
Pronunciation: na-ma-meh
Character: Wall