The 88th Alice was a girl chosen by the White Rabbit to take the "role" as "Alice of Wonderland" before the current one, the 89th Alice. Since she couldn't finish the game of killing the White Rabbit, she failed to become Alice thus, lingers in Wonderland as a Regret, like the other failed Alices.
In her first appearance in Chapter 11, she is a Regret in a perfect human form, and was seen talking with the Cheshire Cat, and clearly expressed hatred toward him. She stated that it was his fault that she couldn't become Alice, while she also stated that she was the closest one to be Alice, and furthermore the best, too. She also mentioned that "Sensei" would have acknowledged her in being Alice.
In a flashback, it was revealed that the reason she failed to become Alice was because she was unexpectedly stabbed by Cheshire Cat, which led to her death.
Informations Source: Wikia