We are a MF couple both 20. Lately I have been fantasising about her getting stretched by other men. Yesterday I went to a sex shop nearby and got a 10inch black dildo. I hid it and at night when she came home from studying at the library I handcuffed her and blindfolded her. I started by eating her out, after she got really wet and horny she started begging for me to put it in, so we started having sex, after she came again, I pulled out the dildo and gently slid it in, I could immediately feel her tense up and she asked me what I am doing. I told her I bet she liked feeling stretched and I started fucking her with the dildo. I started off very slow because it was truly massive, but she got so incredibly wet and horny, and she was moaning so much it was incredible. I genuinely lost count of how much she came. The whole time I was telling her how hot she looked getting stretched out and how hot she'd look with a massive cock. She also squirted all over the place, she had done that before a few times but it was very rare. After we were done she was shaking uncontrollably for a while, she told me she really enjoyed it and I am excited to see where this will lead us. It's safe to assume she's in love with her new dildo.