OK, so my red shirt is:

Name: Thintos

Age: 19

Personality: Over enthusiastic, naïve despite what he's seen in Troy. No-one knows how he manages to smile

Relationship with Ambrus: Originally, hero worship, Thintos was among the first in Ambrus's Trojan brigade, and Ambrus dismissed him as just another devote. However, he has since saved Ambrus's life on multiple occasions, and has proved more loyal than any of Ambrus's soldiers. Ambrus would even be hesitant about selling him out and, if it came to it, he's worried that he would foolishly give his own life for Thintos. 

Reaction if(:airquotes) dead: Though he doesn't admit it, and may not realise it himself, Thintos has become a true friend to Ambrus. If(:airquotes) he dies, Ambrus will likely be crushed, but also confused, as he has never had to deal with these kind of emotions before.

Is that enough, or does he need more detail?