My super kind and timid older sister is very considerate of me and is just kind. So I thought it would be okay to do something a little erotic, so I poked her nipples... Safe! Maybe I can do more than this!? I've been evolving my nipple teasing every day! Then, even though she initially had a slightly disgusted expression, she gradually changed to an erotic face that looked good! I thought, "This is okay now!" and I started teasing everything other than her nipples, building a relationship where I can even have sex with my older sister! Honestly, I was surprised that teasing her nipples, which I started on a whim, had become nipple development! Now, my older sister just needs a light touch to her nipples and her lower body starts trembling, becoming a super sensitive type.
