I find this ship way too cute :3

When they both met, Thorax and Spike were the same age. When Chrysalis planned to take over Canterlot during Cadence and Shining Armor's wedding, she knew she didn't have too much time, so she enlisted all youngling Changelings to her army. In short, most of her army were children, some even weeks old. Following the defeat of Chrysalis and the Changelings, as they were "blown" away by the shield, Pharynx and Thorax were separated, Thorax being flown away up to the caverns of the North. Some of the Changelings didn't survive, but luckily Thorax did by shielding himself and surviving on small creatures. That is until he met Spike.

Thorax doesn't have the same build as Pharynx, as he wasn't born from a Drone father, just a regular male worker. He is more lanky and more flashy, which sometimes makes him a bit insecure. But Spike doesn't mind any of that, and loves him all the same.~