Helena

She is N's allies and have similar abilities for hearing the voices of Pokémon. Anthea and Helena debuted at the end of BW117, where they rescued N after he was injured fighting Colress and Team Plasma in a city. With Ash and his friends in tow, they took N to their secret refuge in the woods where they protect injured Pokémon. Anthea and Helena also appeared in the next episode, where they and N told Ash and company about their past with Team Plasma and Ghetsis. When several Plasma Grunts found their way into the refuge, Ash and his friends battled against the Grunts, and managed to subdue them. After this, N joined his foster sisters, and disappeared into the mist.

When the mist faded, N, Anthea, and Helena were gone, and Ash and his friends found themselves on a wide field, where they saw the Dragonspiral Tower, towering a little distance away. (Source: Bulbapedia)