This article is from the Final-Fantasy and other Square Soft Games FAQ, by email@example.com (Nick Zitzmann) with numerous contributions by others.
It's your choice, really.
At the Returners' Hideout at the beginning of the game, Banon will ask
Terra if she wants to join the Returners. If you say "yes," then you are
given a Gauntlet. If you say "no" to him about four times, then you
instead receive a Genji Glove. Either way, Terra joins the Returners...