Kuja follows when Uendo points out that particular aisle, reasoning that Eidolons quite likely know what they're talking about.

The air is tense. The shelves being empty- that shouldn't be, should it? And of course, when he comes level with the ancient tome in question he has to pause, something he can't quite put his finger on tugging at his recollection. Where has he heard the name 'Tantarian' before? It seems like something he heard once and forgot about, somehow... "Well, this is it..."