Final answer:
The drooly boy who harbors affection for Sophie in the "Keeper of the Lost Cities" book series is Brett, also known as Gurgi.
Step-by-step explanation:
Brett is a Shade, a species with unique abilities, and his endearing nickname "Gurgi" arises from his tendency to drool when excited. Throughout the series, Brett's crush on Sophie Foster adds a touch of heartwarming complexity to the narrative.
As Sophie navigates the challenges of her extraordinary world, including her own burgeoning abilities and the intricate dynamics between different species, Brett's feelings for her contribute to the emotional depth of the storyline. Shannon Messenger crafts a tale where friendship, loyalty, and the complexities of adolescence intertwine with the fantastical elements of the Lost Cities, making Brett's crush a noteworthy subplot in the overarching narrative of the series.