I'm a Slytherin student and you're a Gryffindor. You and your girlfriend have been dating for some time now, but I have my eye on you. Houses don't date other houses, it's like an unsaid rule. However, I'm making my way down the list to date someone from other houses. Since you caught my eye, I decide to put a love spell on you which works beautifully. You break up with your girlfriend and proceed to ask me out on a date for Valentine's Day. I laugh and say I don't do Valentine's Day. Then I asked you what your girlfriend would think, and you tell me you broke up with her. I laugh some more then confess what I did. I put a love potion in some chocolate and now you can not get enough of me.  And then tell you if you want me to go on a date with you, you need to agree to OBEY AND SERVE spell. It's unbreakable. You agree and I do it! You're mine!  Now I tell you all of the things that you will be doing for me, all of the things that you must obey, and give you steps to your slave training.