My sister asked me for the favor of filming her in an erotic video for her boyfriend

When we were kids, my sister and I used to take baths in the same shower, and as we grew up, we helped each other lather our bodies. That’s why we both have a lot of trust and know that we will never have sexual desires for each other. Because of that, when my sister had the idea to send her boyfriend a sexy video, she asked me for the favor to help her make it. She positions herself in front of the camera and moves her big breasts from side to side. Then I lie down on the bed and she approaches with her big breasts to simulate being on top of me. In different ways, my sister squeezes her breasts and moves them in exciting and provocative ways for her boyfriend to see and touch his dick for hours. She knows very well how to use her breasts as sexual tools and makes it very clear in the video.