Character Design for Kakanin Chronicles

Character designs for a series I'm creating called Kakanin Chronicles.
Kakanin Chronicles follows the adventures of the Riveter Bikko, whose job is to defeat Pakobots, mechanical animals of unknown origins.
The Pakobots have become part of the world's daily life, causing trouble ranging from being minor pests to decimation of towns and cities, and it is the job of the Riveters to keep people safe from these events.