Justin Bieber and Selena Gomez Kissing In Caribbean

It looks like all of pop idol Justin Bieber's adoring fans might have to take a backseat to Disney star Selena Gomez.

Though the two young stars have denied reports of romance since they were first spotted getting cozy in December at an IHOP restaurant (with Gomez tweeting "It was just pancakes!" in the duo's defense), it seems they now have some more explaining to do. Bieber, 16, and Gomez, 18, not only rang in the New Year together, but they did so at a party on a private yacht in the Caribbean where they were vacationing together, as reported by The Daily Mail. According to a few well-timed snapshots, they couldn't exactly keep their hands, or lips, to themselves. Two of the photos show the couple draping their arms around each other, while one depicts them clearly going in for a kiss.

The stars may be enjoying the euphoria of young love, but Bieber's twitter fans have made it clear that Gomez ought to watch her back. "Roses are red, violets are blue @selenagomez if you'll break @justinbieber's heart I'm gonna kill you," posted one passionate fan, while another was far less poetic with the straightforward threat, "I'll kill you I swear to GOD!!!" Neither of the young celebs have acknowledged the tweets or officially verified their romance. —KIMBERLY STEELE