The siblings
Friends, I believe siblings are set up in a situation where they have sexual urges they crave to fulfill in the moment.
Aside from my sister, I don't have much interaction with girls. It was my 25th birthday and we decided to go out on a helicopter ride for fun. My sister of 23, is a very modest person due to religion and I never saw her in any sexual way nor felt attracted.
After the helicopter ride, she decided to go into a clothing store to take a look at some things. She took me along the bra and panties section while shopping for other clothes which made me really uncomfortable. She begged me to buy it since she felt too embarrassed to ask our parents. I said fine and told her to not mention that I bought it.
She had a pile of clothes she wanted to try on and the store had a changing room. I thought she would go in alone but my sister told me to come and help her try the clothes on. I was in complete shock and asked if she'd even be comfortable with that. She didn't mind so I went to the changing room.
At first, it wasn't too bad as she just tried on a shirt on top. But then she started to take off her shirt just in her bra. She also pulled her pants down to her panties and I was shocked. I had an instant arousal and tried to hide it but my sister saw the bump. I couldn't lie that I found her breasts and the curvature along her panties absolutely stunning. I apologized and told her to please forgive me.
She didn't seem to mind and then she told me to turn around for a second. She unhooked her bra and stripped down to no clothes at all and told me it's safe to look again. It was really hard and I didn't know what to say in a state of shock. I just complimented her nude body and just said she was gorgeous. I kept staring at her breasts and looked between her legs.
I said nothing as she put her underwear and bra on again and tried the rest of her outfits. We both left the changing room as I was in complete shock and I just bought her whatever she wanted.