Black Carp, Black Koi
noun
In reality, carp are usually black carp. The colored ones aren't as common, people just wish they were.
まごい
The readings for this word are both kun'yomi readings. You've learned both of these readings by now so you should be able to read this on your own.
真鯉の刺青を背中に彫りました。
I got a black carp tattoo done on my back.