I don't think this is a kerning issue, but rather a software one that read "Kurn" as "Kum" when converting the book to Kindle format. There are a bunch of other similar errors like this throughout which had my inner perfectionist screaming in rage, but this one cracked me up because apparently I'm 11 years old.

Or maybe the author actually wrote "Kum" given the other actual typos that aren't kerning issues littered throughout the Kindle version ("Junie Lowery-Johnson", the "Jenolen", etc.).