Every day, I'm tormented by my little sister's ever-growing, increasingly large breasts. When she moves around carelessly, her soft, full tits brush against my arm, stirring emotions I can't control. I catch myself getting aroused, my cock hardening instantly, and I panic, making sure she doesn't notice. But one day, she realizes it. "You got excited from my breasts, didn't you? It's not like anything good will come of this. But fine—my breasts are yours, big brother. Do whatever you want with them," she says gently, yet with a teasing, seductive tone. Unable to hold back any longer, I give in—sucking and groping her tits passionately. She grows more aroused by my actions, and our forbidden bond deepens rapidly.