Unlike the other Sinistrals, Arek acts weary and resigned, perhaps because of the burden of foresight and long experience. He has expressed awareness that humans have the potential to rule themselves and are a serious threat to the Sinistrals' might.
Late in Lufia II, Daos claims that Arek has the power to twist fate. The crisis of the Sinistrals was supposed to bring out good superbeings as well as evil ones (the Sinistrals); however, Arek somehow prevented the good superbeings from appearing.
In Lufia: Curse of the Sinistrals, Arek shows satisfaction that Erim was the first Sinistral to express attachment and to willingly sacrifice herself for Maxim and humans in general respectively. During the game's alternate ending, he vows that Erim's sacrifice will not be in vain.
So far, Arek has not done anything to threaten the human race - he only ordered the Sinistrals to investigate the resonating Dual Blade, but Daos ordered them to terrorize and destroy humans. Arek has also been shown in the opening of Lufia II to be able to warp the Dual Blade to his view.