Wondering if the goodnight kiss your new guy gave you last night was a tepid formality or a sincere expression of how into you he is? Well, according to Cosmopolitan, there's a surprisingly little trick that helps you decode all the feelings behind a kiss - and it has to do with foreheads.

Cosmo contributor Lillian Glass says that if you and your guy touch foreheads while you kiss, it's a sure sign of genuine intimacy. Citing the royal kiss shared by Prince William and his newly-minted bride Princess Catherine Middleton as an example, Glass says that touching foreheads shows comfort, affection and commonality. "Their foreheads are pressed together, which means they're like-minded and very into each other," she explained.

Even though the royal couple didn't embrace when they kissed - which some took as a lack of excitement - Glass says she's confident that they're truly in love. " They knew they had to keep their bodies facing the crowd,"  she said. " So what's more important to look at is how their bodies lean in towards each other and how they stood shoulder to shoulder, signs they are equal partners and very in love." So next time you're sharing a kiss with that special someone, pay attention to body language to see how he's really feeling.