"Laguna Beach" Star Goes Down on Hayden

With her 18th birthday just 42 days away, Hayden Panettiere's boyfriend, former "Laguna Beach" star/"TRL" host Stephen Colletti, appeared to be practicing to pop the question! I now pronounce you man and jailbait!

While sunning her nubile young flesh on Venice Beach Monday, the bikini-clad "Heroes" star played handsies with her kneeling, shirtless, 21-year-old lovah. Hopefully they used protection, er, sunscreen!

Luckily, Hayden and Stephen kept their seaside shenanigans PG-13 -- for now!