[ Does this person not realized what Setsuna means when he sworn his sword to him?

Well, since it's Setsuna, it's likely that the Meister never explained anyway... Which mean, Tieria is going to have to. ]

You agreed to it when you allowed Setsuna. He will only offer such oath if he thinks you're in need of protection, not the other way around. If he deemed you so, then so will I. If you don't like it, take it up to him.

[ Taking a sip from his glass. ] Sit down, Gilgamesh.