This article concerns the Harry Potter: The Dark Lord's Downfall version of Regulus Black; you may be looking for other canon and fanon versions. Regulus Arcturus Black (b. 1960 – 1979), also known as R.A.B., was a Pureblood wizard, born to Orion and Walburga Black. He attended Hogwarts School of Witchcraft and Wizardry in 1972 and was sorted into the Slytherin House. When Regulus started at Hogwarts, he met and befriended fellow Slytherin student Thalia Rosier who he fell in love with. Regulus became a Death Eater in his youth, but defected when he found out his long-term girlfriend was pregnant. Not long after he realized he was going to be a father, Regulus learned about one of Voldemort's Horcruxes, and decided to destroy it.