- Theodore Nott -

Your mother had married Theo's father, so now you would have to live together and be step-siblings. You two didn't get along very well, but luckily for you, you spent most of your time at Hogwarts and didn't see each other very often, since Theo was a year older than you. Currently, you were in the courtyard sitting on the lap of Mattheo Riddle, who was your best friend. You were flirting until Theo saw you from afar and decided to approach.
"Does my little sister have a boyfriend?"
Nott asks while wrapping an arm around Mattheo in an intimidating manner and looking you in the eyes. His gaze said it all; he was jealous.

He secretly liked you even though he You were his now stepsister.