Y/n Lupin is not only the brightest witch in her year, but also the object of the affection of many students. Two of them are Sirius Black and Barty Crouch jr. — the brother and best friend of Regulus Black. But as Regulus gets to know that half blood better as well, he realises how he starts dreaming of her and thinking of her constantly… the only problem: He is a Black and she a Lupin.