First dare with Flanna and Claire

For our first dare as a group we wanted something a bit more tame. They both saw me naked but it was dark. I saw Claire naked and we had sex even if we didn’t finish but Flanna was a bit shy around me and also Claire even after what we did. Flanna generated a dare more tame and it was:
Where's Your Towel
Remove all of your clothes and wear a towel.
Since my parents were away, we decided to do it at my house and since they both already saw me naked, we decided that I should go first. I went to the bathroom and stripped naked. I grab a towel, tried to make a big a stomach as I could and wrapped the towel around me. I went back to the living room where both girls were waiting. They both smiled and made small compliments.
But Flanna asked: “How can we be sure that you’re naked under the towel.”
“You can’t. You have to trust me.”
Claire tried : “But we already seen you naked so you can show us to be sure.”
“Nice try but no.” I turned around and suck in my gut. That loosen the towel and as I walked, it slowly became unraveled. I thought it would hold anyway but two steps before I turned in the bathroom it finally fell.
I heard a wow as I bend over to pick up the towel and I glanced at them as I entered the bathroom and they were both enjoying the view of my ass with a big smile on their face. I got dress and went back to the living room. They were both still smiling and commented that I successfully completed the dare.
Now it was they’re turn. They couldn’t decide how should go first and we agreed to flip a coin.