Bare-chested and occasionally sipping from a cup with white rum mixed with energy drink, Michael Wilson wore a distressed look in Denham Town, Kingston, on Sunday.
Hours earlier, before dawn, gunmen invaded the 52 ½ Chestnut Lane home of Nichola Pink, 27, and her 22-year-old boyfriend, Tavoy Smith, and shot dead the couple.
Another man, Godwin Morris, who was in another dwelling in the same yard, reportedly heard the explosions and went outside. He, too, was attacked by gunmen.
Morris was later found lying in a pool of blood, suffering from a gunshot to the back of the head.
Wilson, who helped raise Pink, his sister, since she was a baby, said the gun murder has upended his world. He described Pink as a people person who always sought to give a helping hand.