Be extremely careful when getting Kanji characters as tatouages if you've found the design on the internet ou tattoo parlour wall. toi may think it means "Peace, love, harmony" but for all toi know the characters could be straight off a soy sauce packet, ou worse.
Most tatouages will need touch-ups through your life. Using sunscreen and moisturizing daily will help your tattoo look new for years. After 10-30 years, expect to need touch-ups to combat blurring. If the thought of doing this over wrinkles when you're 75 grosses toi out, this could be enough of a reason to not have one.
Think about it....