Gear Ratio's nickname is Zero. It used to be his name but I've decided that's a really cringey-a*s name lol.
Zero was born with a rare disease that makes his immune system super weak. One of the things it caused was that he never grew a coat or tail. He grew up living in a clean room, but he eventually had a spell cast on him that protects him from sickness. It has to be refreshed every once in a while and near the end of the spell's life, he starts getting sick really often until he just has to either get the spell cast again or start quarantining himself.

I don't know if I'll ever use him again or not but if so, he'll probably get a redesign.