"I needed a song for this movie that, if a boy that you liked knew every word to, you’d be incredibly impressed, and you’d know he had good taste," she told EW.
Indeed, Ryan knowing "Stars Are Blind" — and unashamedly singing and dancing to it in public — reinforces what has already been established about his humor, warmth, and, importantly, nontoxic masculinity. We get to watch Cassie fall under his spell — and follow right along with her.
But we're being set up. The scene is lingering in our minds when, later, we discover, along with Cassie, that Ryan was actually present when her friend was sexually assaulted.
He's just as terrible as the other men she's encountered, and the revelation is a gut punch that reinforces the insidious nature of rape culture and toxic masculinity. The heartbreaking message is made all the more potent because all the hope and joy generated with "Stars Are Blind" is proved to be false.