Honestly, I love tattoos and they're a lot of fun! Most people on here are going to tell you not to get one unless it has meaning. I disagree in a way. Yes, I think it is fantastic if you have a meaning or story behind each tattoo but I don't see anything wrong with getting something just because you like it/it looks cool provided it isn't something like profanity, heroin needles, naked women (or men...if..your into that sorta thing..?) or anything vulgar.
Both of my tattoos have meaning to them. One is weird because I disagree with walking into a tattoo shop, picking one off the wall, and getting it inked on HOWEVER the one on my left arm IS off the wall. It still, though, has a lot of meaning to me.
Neither one of my tat's are magic related...my next one will be. Both of my tat's ARE impulse tattoo's. I'll probably get bashed for that. One of them, like I said, was off the wall and the other I walked into the shop, had it designed, loved it and got it put on my leg all in that same night. I know, because of the meaning behind each, that I will never regret either one.
A tattoo is something YOU have to like. I posted a thread a while back asking for tattoo ideas. Honestly, YOU have to come up with the ideas yourself because it is going to be on YOUR body for the rest of your life. I like the design you posted up. I think it has potential to be a way sweet tat but ultimately, it doesn't matter what any of us on this forum think. It's all up to you.
My advice to you would be to take that to a tattoo artist. Have him put his artistic spin on it (it has to be made tattooable - they can't just ink a drawing on you). Have him put colors you want into it, draw it up and make it look EXACTLY what it will look on your arm. Take that drawing home and stick it to your wall where you see it everyday for a few months. If that drawing doesn't get old and you still like it after a few months, then decide if you are going to get it tattoo'd.
One last thing - I don't recommend getting it on your forearm. That is going to be visible if you are wearing anything with out long sleeves. Most employers aren't going to like this and it could hinder you from a career in the future. One of my tat's is on my left shoulder. All I have to do is wear a T-shirt and it is invisible. My other is on the back of my right calf. Most careers are going to require me to wear pants (I'm actually going to be a chemical operator where I will be wearing cover-alls) so anytime I am at work, it will be invisible. My next tat is going to hopefully be a quarter sleeve on my right shoulder which still will be invisible with a T-shirt on.
I hope I helped some. Just give it some thought - the design, the location, the size, everything. You will know if it is right to get the tat!