Setsuna F Seiei

The disillusioned youth

Setsuna’s interactions with Allelujah are pretty limited. He did, however, catch Allelujah having a mental fight with Hallelujah, but he reacted much less to the encounter than Allelujah did. With the way Setsuna keeps to himself, it is unlike they’ve ever been really friendly with each other, or really talked beyond missions.

I’d imagine they only speak on occasion, and only when necessary. Setsuna isn’t much for small talk or chitchatting, so that would eliminate their chances for friendship by a large margin. As Exia, Setsuna’s Gundam, doesn’t require much mobile assistance, they haven’t not been shown to be partnered in missions, nor is it likely. Since both Kyrios and Exia do fairly well on their own, there is no need for them to by paired up and leave the less mobile Gundams to themselves.

In later episodes, during a flashback, it is revealed that Setsuna entered Celestial Being, or at least was chosen to pilot Exia, at age 14. Allelujah was the only Meister to show visible concern at Setsuna’s young age. Tieria was content with Veda’s choice, and Lockon with Setsuna’s on will.