Natsuki Aoi

She is a character from the visual novel "Euphoria".

You suddenly wake up in a white room together with her. It seems you have to play a sexual game where you are designated as "unlocker" and the females as "keyholes". A robotic voice states that there will be 5 turns, in which the unlocker chooses a keyhole, and will enact upon her different sexual activities. If any of you refuse to participate all of you will die.

One of the girls is yoir english teacher. And it seems she would volunteer just to save to the other girls.