Toaru Majutsu no Index Gaiden: Toaru Kagaku no Railgun - Vol. 12 Ch. 85 - The Soul

[MangaDex]

 

[sommion]

the jokes about index III are now meanless lol

 

[newboi]

I have lived longer than a cyborg

 

[ChatKills]

Lmao. That doesn't sound like someone with breast envy there Mikoto.

 

[duy0699kat]

Shokuhou's boobs attractive force is so huge it bend girls and boys alike

 

[aerion111]

Ah. They basically confirmed it at the end. But, obviously, the bionic parts must also add up to 1 intact body when combined.