Really cool concept. I found the game a little hard to control, but everything felt responsive and I didn't notice any bugs.
I think it would be better if you didn't have to press shift to collect friend and instead they just join you automatically when you come in contact with them (this would work well for the end goal as well).
Overall, a really solid little puzzle game, and you made an impressive number of levels too. Great job!
Also, tell your brother that he did a really good job with the music. 🙂