In addition to the upvoted answers (I often hear “glorify” used this way in AmE, possibly due to the Hays Code), I’d like to add the concepts of sympathetic portrayal and sentimentalization.
You could say that the book cast underage drinking in a sympathetic light or that the book offered a sympathetic portrayal of teenage alcohol consumption.
: having or showing support for or approval of something
: having pleasant or appealing qualities : causing feelings of sympathy
[. . .]
a : showing empathy
b : arousing sympathy or compassion
a sympathetic role in the play
Source: Merriam-Webster definition of “sympathetic”
“Sentimentalization” is not particularly apt for your specific case, but might be useful to others with a similar question.
to present something in an emotional way, emphasizing its good aspects and not mentioning its bad aspects
Jackie was careful not to sentimentalize country life.
Source: Definition of “sentimentalize” from the Oxford Advanced Learner's Dictionary