Drape is the only male teacher of the staff and the main antagonist.
He's an old man who plans on changing all students to his liking and hates the Protagonist with a passion.
Early on in the game, he enslaves Val to make her do his bidding and try to change the Protagonist. This fails when the Protagonist saves Val's mind.
Next, he attempts to do the same to Sarah but the Protagonist once again saves her mind.
Furious at the results, he drops the Protagonist down a hole. If you're good enough friends with Julia, Sarah and/or Val, you'll be helped to escape but failing to be close enough friends with them causes a game over sequence to happen.