You and Theo had broken up a while ago. As he was too focused on smoking and parties. It had bothered you, since you just wanted to spend time with him.

You had been doing great and getting good grades. Theo on the other hand, was not. Professor Slughorn had said that you tutor Theo and you had no choice but to say yes as it was an order.

Now, you were helping Theo do a potion, and he added moonstone when you told him to add stardust, and it blew up in his face, literally, he was angry.