Katy Perry is a heroine to a huge number of fans around the globe and seems to particularly connect to the young. Those who were children when she first emerged onto the world's stage are a little older now, and so they've reached an age where they can choose to have tattoos if they wish to. We imagine that's what's gone on here.
Perry looks a little more serious here than she usually does in everyday life; the 'Firework' singer is generally seen with a smile on her face, loving life. She's equally capable of this kind of smoldering expression though. Many people out there have kissed a girl and they've liked it, but how many of them have had a tattoo of their favorite singer on their skin, and liked it just as much?