I nominate Nishi Joichirou (or Joichiro) from Gantz for the Best Male Support category
Because...I just love him XD nah.
He's a real cold but (very very ver- *gets shot*) cool sadistic jerk, but deep inside he actually has a soft spot, which sometimes will give me impressions of Tsundere. Despite being in such young age (he's a middle-schooler) he was able to see how messed up the society was, and do thinks maturely. His past from Gantz Minus made his character more appealing (even if it's not canon).........and I'm not gonna spoil anymore, lol