It can be an option because it's just a game, choose one permanent choice out of 2+ and the char is now a trap, you have the power! . Thought somewhere the dev mentioned the trap is one of the current students at the school which I'm too lazy to look for through all these last pagesHow can being a trap be an option?
You either are or aren't. And a 'would you like for Eve to be a trap' choice at the start of it would ruin the flow. Now if the Principal/Annie path goes full Bible Black that would at least explain it.
I also just remembered the bank lady that was in the game from the very beginning, or the chick from the library.