Okay, from my dictionary, I have several kanji that will work. (You do know kanij is Japanese, right?)

孑孑 (boufura or boufuri)
This word can mean “mosquito larva, wriggler, or maggot”, but it seems kind of vauge to me. Most people who can read it will think it’s the first meaning.

蛆虫 (ujimushi)
This word means ether “maggot, or abusive word.” The first kanij means “worm, grub, or maggot” while the second kanji means “insect”. (Although I’m not sure if it can mean”abusive word”, or if it’s used as one.)

蛆 (uji)
This kanij by itself just means “maggot, or grub” and if I was getting it in a tattoo, I would proboly pick this one.

But it all depends on what you want it to say. If you want it in a sentance, I think the second one would be better, but if it’s by itself, the third would be best. Although I’m still a student with a LOT to learn, I’d show someone else the kanji I just listed to make sure.

On a side note, why the hell do you want a tattoo that says “maggot” in Japanses? Just asking.

maybe its his nick name because he is not very well hung LOL

Depending on where he wants tattooing – might be an awful image in your hands.

😀

Matthew