Incredible experience! It reminded me of Valve's sense of humor in HL and Portal. The game concept is very clear (no spoilers) and the look fits the experience perfectly.
WARNING: minor spoilers ahead. The personality of the characters is differentiated, which for such a short game made me feel that its world was greater and rich. The third character deserves its own game; holly molly, that's world building! Also, I think that you did really well at the mechanics, in the sense that they extend the length of the experience by being combined; so A, B and C can become AB, AC, CB and ABC too. The end might look a bit tedious for some, but I found really enjoyable because I found myself playing hard because I wanted hard to play... So self-reference gets into the gameplay itself, not just into the story, and makes the experience very rounded. And the very end, I guess you might see something like that coming, but it felt like a confirmation that I was being absolutely trolled and was enjoying to be so. So 5/5 from me!