Toga Tenkuji

Klien Samdman raised Toga from a very young age to be the best stratagist, the best fighter, and essentilly the best at everything. But there was an area of Toga's education that Sandman utterly failed to teach, emotion and simple compassion. 
 
Outside of battle, Toga seems an affable, friendly, if extremely dense person. In  battle however, he becomes a cold, ruthless killer, willing to win by any means at his disposal. Even if it involves the sacrifice of one of Sandman's maids. That particular incident involved a shopping trip gone horribly wrong when a zeravaier "bomb"  touches downin the middle of the city and starts to cout down to detonation. Once the Gravion mech is ready to destroy the zeravaier the rest of the team makes the observation that one of the maids was almost directly in the line of fire, Toga however, does not see this and continues to aim. Had Eiji not jumped out of the leg of the Gravion and rescued the maid Toga would have shot clean through the young girl to destroy the zeravaier. 
 
The second incident where his thoughtlessness harms other is when he shows a video to Leele that reveals her to be Klein Sandman's niece, and the daughter of the perpetrator of the zeravaier attacks. This thoughlessness shocks Leele into attempted suicide and a catatonic state that lasts for several episodes. It is after  this incident that Eiji rightly calls Toga a heartless, cruel, THING. Denying that any actual person could be as utterly thoughtless as Toga. 
 
Toga promptly suffers an emotional breakdown that only gets worse duringthe next zeravaier attack that costs the life of one of Sandman's maids. She sacrificed herself to save him. 
 
Predictably however, Toga is broken of this breakdown by Eiji, who litterally beats the lesson into Toga with his bare fists.

 
Leele later forgives Toga and actually seems to love him by the end. What is even more surprising is that Toga actually seem to return the affection by the end of the series, even though he is still practically a newborn in regards to the way the world works.