Tahiri Veila is a human Jedi raised by Tusken Raiders on Tatooine, introduced as a child in Nancy Richardson's Junior Jedi Knights: The Golden Globe (Boulevard, October 1995) and carried through nearly twenty years of Legends publishing to the end of the line.
Shaped
Her defining ordeal is in the New Jedi Order series: captured by the Yuuzhan Vong, she is subjected to a shaping procedure intended to write a Vong warrior personality, Riina Kwaad, over her own. The process is not fully undone. She spends subsequent books with two sets of memories and two people's reflexes, and the writing treats this as a permanent condition rather than a problem to be solved in one volume — one of the more genuinely unsettling things Legends did to a character introduced in a children's book.
Anakin
Her relationship with Anakin Solo runs from the Junior Jedi Knights books through to his death at Myrkr, and his loss is the hinge of everything she does afterwards. In the Legacy of the Force series that grief is what Jacen Solo exploits to recruit her: he offers her the possibility of going back through the Force to the moment before Anakin died. She becomes his apprentice and, on his orders, murders Admiral Gilad Pellaeon.
Afterwards
She is tried for that killing in Fate of the Jedi and acquitted on a technicality rather than exonerated, and the novels are careful not to hand her an easy redemption. She ends the Legends timeline as a Jedi again, which the other Jedi have not entirely agreed to.