Becky Albertalli's The Upside of Unrequited
I really, really liked Albertalli's first book, so I was very much looking forward to her second, and it did not disappoint. It's one of those lovably chaotic and relatable and heartwarming-but-not-TOO-cheesy YA books, with a really cute and compelling narrative voice. It centers on a teen--the chubby one of a pair of twins, who always has a hopeless crush and never does anything about it--and what happens when her sister gets her first girlfriend. Lots of good diversity here too. Super nice fluffiness. A-.