Assigned group project turned into a library threesome

I am 19F, and one of my university classes had a final project instead of an exam. I was randomly assigned to two other guys. Fortunately, they were willing to contribute, so we decided to reserve a private room in one of our university libraries every week to work on it.

We actually became friends because of it. We would talk, get food after finishing our work, watch anime, and lightly flirt with each other. On the last day, they snuck in alcohol to celebrate us finishing our project. The atmosphere was pretty depressing because the three of us actually became friends with each other.

With the courage of alcohol, despite my better judgment, I kissed one of them. Then I felt bad for leaving the other guy out, so I kissed him too. Before long, we ended up having a threesome in that room. While I have had other threesomes before, a library is definitely the weirdest place to have one.