Its nothing malicious, don't worry. Its something I've seen before too =P This is why I love having a mac never the fear of opening somehting malicious by accident.
it's not humans 2 inanimate objects 'having some fun' - though the sound effects are quite real sounding
Its just a media file my friend,everything is OK with it! (It will open with Quicktime or some other alternate program (Whatever you have ".mov" assigned to))