The Japanese kanji means sky or heaven. It is displayed when Akuma, from the streetfighter series of games, K.O’s you with his finishing move ‘Raging Demon’ or Shun Goku Satsu which literally translates to ‘Instant Hell Murder’. Scary!!!
Below the kanji is how to perform the move. I would of liked to put the kanji on the back of the t shirt but there isn’t an option for that on Red Bubble as far as i know. Maybe they will add the option in the future.