About the ‘green’ ink, it’s probably because the tattoo you saw was old. When a tattoo is a couple years old and is frequently exposed to sunshine without protection, the black ink will turn into a blue-green-ish color. That’s why it’s really important to put sunscreen on your tattoo when you go into direct sunlight.
Also, about the ‘bleeding’ lines. I’ve said it before, but there are soooo many people that don’t know this : if you lines ‘bleed’ (wich means, when your tattoo is healed, the lines are not so crisp or clean anymore : it kinda spread under the skin) it’s not because of the artist or his/her technique, it’s because the person put TOO MUCH CREAM for the healing process. While the tattoo is healing, it’s important to put cream on it in THIN LAYERS, so the tattoo can still breathe and heal properly.
So, if you take good care of your tattoo you won’t have any problem with it and it’ll still look good through the years!
Hope it helped 🙂 Xx