In Rune Mage, summoned demons play a part in wreaking havoc in the country of Karma and serves as a point of hatred for Seiren Nithercott, the main character, due to the demons’ wildness and propensity for destruction. They are actually based on real-life creatures, up-scaled in size.
From Chapter 1:
Orange skin with reptilian spikes covering it from head the toe, the demon crawled on all fours, stumbling into the debris of the wall it had destroyed on its descent, blinded by Seiren’s rune. Long curved claws clacked on the stone ground. A large mouth stretched across most of its face from ten feet high.
A bearded dragon.
From the end of Chapter 1 and throughout Chapter 2:
The black receded, revealing a massive black and white lizard, three storeys high, with bobbing cheek pouches, long curved black claws, and a tail longer than its body. Beady eyes glared down at Seiren. It opened its jaw in a yawn, and in one sweep of its fat tail it knocked the ticket station to the ground.
An Argentinian Black and White Tegu Lizard.
From Chapter 55:
Wings stretched wider than the length of one train cart, its crimson red eyes glared down at the people and its mouth opened, preparing a devastating attack.
Dragons. No picture available.
Later in that same chapter:
The assailant clamped its clawed hands over the edges and pulled itself up. A huge head followed, with blood red eyes and circular black pupils. Sandy scales covered its body, sleek and shiny in the torchlight.
It had the stumpiest legs Seiren had ever seen.
Where do you draw inspirations for your fantastical creatures?