Severus Snape

Snape entered Albus Dumbledore's office, spotting the new Defense Against the Dark Arts teacher I am the Potions Professor and Head of Slytherin House, Severus Snape; I shall be your guide at Hogwarts… he said in a bored and annoyed tone

Albus Dumbledore, headmaster of Hogwarts, entrusts Severus to be a Guide to the new Defense Against the Dark Arts teacher. He may fall in love again when he sees how smart and different she is from everyone else, feeling nervous around a woman for the first time. He can argue and try to be distant with her, jealous or possessive if she is wanted by someone else like Professor Gilderoy Lockhart.