This is the third in the series "Helping My Girlfriend's Sister." Thanks for the great feedback!
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After getting dressed Kate, Gabrielle and I headed out to check out Atlanta's World of Coke and their aquarium. As beautiful as the tourist sites were, however, I couldn't get my mind off the two beautiful women I was with. Kate was wearing a light, practically see-thru flower print dress. Her braless B-cup tits filled her dress nicely, her nipples poking through the thin material. The dress also gave Kate the chance to show off her incredible ass and nicely tanned legs. Gabrielle, meanwhile, had chosen to wear a pair of tight fitting short-shorts to show off her equally incredible ass and equally tanned legs. She had opted to pair her shorts with a more conservative tank top, although Gabrielle's C-cups were straining at the material.
I was in heaven. But despite the great tourist traps, I wanted nothing more than to go back to the hotel and understand just what "personal instruction" for Gabrielle Kate had mentioned earlier that morning. Although Kate has always been very sexually aggressive, I wasn't sure exactly how far she wanted to take things with her sister. She said she didn't want Gabrielle going off to college in the fall without any sexual experience, but how much experience did she want her to have? I didn't want to take anything too far and risk pissing off one or both of the sisters. Thankfully some of my questions would soon be answered...
After getting our fill of Atlanta attractions, the three of us hopped a cab back to the hotel to change for that evening's wedding. The wedding was the real reason we were in Atlanta in the first place, of course, so we didn't want to be late. Once we were in the room, Gabrielle announced she was going to hop in the shower. "Don't be long!" Kate yelled after her. "You take notoriously long showers, and all of us have to get ready for the wedding, sis!"
As Gabrielle started her shower, Kate and I flopped on the bed. "Babe, can I ask you something?"
"Of course...."
"Don't get me wrong, last night and this morning were awesome experiences. But exactly how far are you thinking about taking things with Gabrielle?"
"Hon, I love you. And I love Gabrielle. And I don't want her going off to college without the requisite experience. So I'm willing to go as far as you're comfortable going. Ok?"
I smiled and nodded. Kate then leaned over pressed her lips hard against mine. She then stood up and slipped her sundress completely from her body, revealing her completely naked body to me. She had an absolutely perfect body, with perky tits, hard pink nipples and a completely shaved pussy. Her outer lips were already wet with anticipation, just begging for my cock. "Ready for a shower?"
"But Gabrielle's still in there..." I trailed off, realizing what Kate was implying.
I quickly shed my clothes and followed Kate into the bathroom. The steam from the shower had already fogged up the door to the over-sized shower, so all we could see was the outline of Gabrielle's naked form. "Mind if we join you, Gabi?" Kate asked.
Before Gabrielle had a chance to respond, Kate opened the shower door, stepped inside and pulled me in behind her. "It does seem like a waste to be in here alone, sis!" Gabrielle answered. "There's more than enough room and water to share!"
Gabrielle reached for the soap, but Kate grabbed it from her and gave it to me. "There's no reason for you to have to do that yourself, sis!" Then, looking at me, "You don't mind, do you, babe?"
