The pressure of "fitting in" vs. being with someone outside one's social circle.
These are the modern equivalents of the love letter. Ignoring them makes your story feel dated.
They were in Leo’s driveway, supposedly studying for a mid-term, when he reached for his highlighter at the exact same moment she did. Their hands brushed—a simple, accidental touch they’d experienced a thousand times before. But this time, neither of them pulled away.