Just because you grow out doesn't always mean you have to grow up. And even if you DO grow up a little, you're free to choose the ways in which you do it. You're a unique individual. Don't let society dictate for you what you like and what you don't like. Having your own opinion is a freedom we take for granted here in the western world. Cherish it. And don't be ashamed of who you are. If someone laughs at you for liking Pokemon, just laugh back and say, "yeah, I'm a nut, I guess. But I'm a happy nut!" That's what I do, but individual results may vary, lol.
Btw:
Age: 23
Poke-addictions:
--All the video games (Gimme!!)
--The manga
--I saw the first season of the anime and then I was too busy to watch TV for a while so I stopped watching after they got too far in the series for me to keep up. I might still like it. I don't know. :/