I actually found it after listening with head phones and trying to write down the lyrics, then searched those lyrics online. It was "Fire and Ice" by Jessie Villa 🙂
Thank you for your reply, regardless! Just finished ep1, heading for 2 now. I actually found Last Human before Serenity, so I'm going to do another playthrough of that after ep2 cuz I probably missed a lot of references. Last Human looks great btw, it's very clear you've learned a ton and have grown substantially since Serenity ep1. Keep it up. Looking forward to more.