Grumble

Commentary:

The first appearance of Red’s car and Magenta’s house. It looks a lot like Blue’s house but it’s pointier at the top. Grey balloons because for colorful people grey things are apparently festive.

The color of glass is the same as the color of water, which is true, even if that color is completely transparent in the real world. Here everything is just blue.

Yellow is nervous because he has a crush on Magenta.