This is in chapter 15 part 1 - This is a 9S gameplay. Go to flooded city and explore the broken flight unit. 9S will discover that the flight unit is 2Bs. He will hear the last message of 2B for him. Looks like she likes him a lot. She even calls him nines
2B is an all-purpose battle android, deployed as a member of the automated YoRHa infantry. She is equipped with a multitude of weapons for close quarters combat and can attack from range using the Pod support system. Her eyes are obscured beneath her standard-issue military visor, which she rarely removes.
Source: https://nier.fandom.com/wiki/YoRHa_No.2_Type_B
9S is a scanner type android who served during the 14th Machine War. He has an attack function, but it is an android that specializes in investigative purposes—a member of the automated infantry squad, YoRHa, who triumphs in hacking-based information collection.
Source: https://nier.fandom.com/wiki/YoRHa_No.9_Type_S
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