Well, one theme is the idea of transformation. Just like the new year changes the calendar, the characters might be changing in some way, and the kiss is a moment of that change. Another is the theme of shared joy. Everyone around is celebrating the new year, and the couple sharing a kiss is adding to that shared sense of joy. And then there's the theme of a moment frozen in time. The New Year's kiss is a special moment that the characters and the readers will remember, much like how we remember the transition to a new year in real life.
One common theme is new beginnings. The New Year represents a fresh start, and the kiss in the fanfiction can symbolize the start of a new relationship or a new phase in an existing one. Another theme could be the magic of the moment. There's often a sense of heightened emotion and anticipation as the clock strikes midnight on New Year's Eve, which is reflected in the kiss. Also, themes of love and passion are prevalent. The characters may finally express their long - hidden feelings through this New Year's kiss.
Some common themes include celebration. It's New Year's, so the characters are in a festive mood, and the kiss is part of that celebration. Reconciliation can also be a theme. If the characters had a fight or were estranged before, the New Year's kiss can be a way of making up. And of course, the theme of hope. The new year brings hope, and the kiss can be seen as a sign of a hopeful future together for the characters.