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$1899
Picture Book · Ages 4–8 · May 12, 2026
The Underwearwolf
By Charles Santoso · With Gideon Sterer
A kid's full moon undies transform him into an underwearwolf.
32 pages
4.1/5 Goodreads · 144 ratings
$19.99Save 5%
Hardcover
CS
Children's book Illustrator
Verified creative
Charles Santoso
Biography
Charles Santoso (Chao) loves drawing little things in his little journal and dreaming about funny, wondrous stories. He gathers inspiration from his childhood memories and curiosities he discovers in his everyday travels. He has illustrated several picture books, including The Snurtch and I don’t Like Koala—both written by Sean Ferrell, Ida, Always—written by Caron Levis, which was mentioned in the New York Times as “an example of children’s books at their best,” Peanut Butter & Brains—written by Joe McGee, and Penguin & Tiny Shrimp Don’t Do Bedtime—written by Cate Berry. Also a New York Times bestseller Wishtree by Katherine Applegate and A Boy Called Bat by Elana K Arnold.
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At a glance
Book Stats
0
Authored
34
Illustrated
39
Collaborators
Picture books
26
Graphic novels
1
Chapter books
7
Publishing timeline
Books published each year, stacked by book type.
Publication timeline from 2015 to 2026.
Book mix
The share of the catalog represented by each book type.
Book type breakdown: 26 picture books, 1 graphic novels, 7 chapter books.
34
books
Complete bibliography
All Charles Santoso Books
Every title in the Bookroo library, ordered from newest to oldest.
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Baby animals are kissed goodnight, leading to a final sweet dream for a little one.
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Discover the extraordinary world of dogs through playful poems and surprising facts.
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Separated by migration, two storks must find a way to keep their bond alive across continents.
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As wildfires rage, a wombat's burrow becomes a refuge for desperate animals.
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Willodeen
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A girl must solve the mystery of missing creatures to save her village.
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The Bookstore Cat
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Explore a bookstore cat's whimsical day from A to Z.
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This Way, Charlie
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A blind horse and a gruff goat forge an unlikely friendship tested by life's storms.
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Watch Out for Wolf!
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Three little pigs plan a party, but can they outsmart the lurking Wolf?
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Dandy
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A father struggles to remove a weed from his lawn, but his daughter's attachment to it complicates the task.
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Bat and the End of Everything
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A young boy struggles to cope with the impending departure of his beloved class pet and the challenges of caring for a wild animal at home.
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Dragons Get Colds Too
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A dragon with a cold sneezes fire. Can you help him recover?
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No Boring Stories!
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Misfit animals defy boring tales to create their own wild adventure.
Graphic Nov.
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A bedtime story with fireworks and sharks, but no sleep.
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Bat and the Waiting Game
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A young boy named Bat cares for a baby skunk named Thor and navigates the challenges of family and friendship
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Aliens invade, demanding 'Sploink' and spreading chaos. Can peace be restored?
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A young boy named Bat cares for a baby skunk after its mother is killed by a car
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Un niño llamado Bat
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A boy has one month to prove a skunk can be a perfect pet.
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The Snurtch
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A mischievous monster disrupts Ruthie's school day, testing her self-control.
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Spy Guy
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Can a clumsy spy uncover the secret to stealth?
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Best Friend Battle
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Sylvie battles to outshine Georgie and win back her best friend with a grand birthday plan.
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I Don't Like Koala
Picture Book · Ages 4–8 · 2015
A boy struggles to escape a creepy toy koala that won't leave him alone.
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An otter's life changes when she's rescued and becomes a mentor.
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Love, Grumble
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A grumpy troll learns love isn't as bad as he thought.
Creative company
Collaborators
The authors and illustrators who share the credits across Charles Santoso's books.