Sean Kingston -- LET'S-A-GO!!! Get a Mario Kart Tattoo

Mama mia! Sean Kingston loves Mario Kart so much ... the singer tattooed a giant freaking memorial to the video game on his arm ... and the pics are kind of awesome.

King posted the photos on Twitter the other day -- showing his new suped-up Mario Kart inkjob in progress inside his L.A. home ... courtesy of a local tattoo artist named Peter Koskela.

We're told the tat cost Sean a total of $1,250, and took 5 uncomfortable hours to complete.

File it under things Sean will probably regret in 20 years.

Aw-wawawawawawawa.