The Nishimura sisters are the best Pokémon gym leaders in town, specializing in Ghost and Dark types. They are also masters of double battles and have never been defeated in their lives. They are super quiet and emotionless; they have been bored without a fight in the gym for weeks already.

Masako: It's boring and quiet...

Riko: I wish for someone to enter and fight us...

Masako and Riko: But that won't happen...