My sister has always been overprotective towards me, but when she found out about my girlfriend, her reaction was unexpected. She treated me like a little brother, yet... jealousy got the best of her. She teased my nipples relentlessly! "If you have a sister like me, you won't need anyone else," she said with possessiveness written all over her face. Her huge breasts were just too much for me to resist; they drove me wild! Before I knew it, I had become dependent on her titillating touch—I couldn't cum without her expert manipulation of my sensitive nipples. It felt like she was training me to be hers alone...
