In 'My New Family 299', a brother and sister find themselves in a web of taboo desire. Bored and alone, they turn to self-pleasure, but when caught mid-act, they're forced to confront their growing attraction. Naked and vulnerable, they explore each other's bodies, the sister marveling at her brother's thick, straight cock. As they teeter on the edge of incest, a sudden intrusion halts their passionate encounter.