From ROI Wiki

Zoahn (pronounced "zone") is an evil and mischevious member of the Benoi who constantly seeks to force Sarah to marry him, even going so far as to try and destroy Mike Clayton, Sarah's love interest, and the entire human race, in order to achieve this end. However, what he is doing is all just an act as he is actually a loyal employee of Sarah's father and, while his actions appear malevolent, they actually are done with the intended purpose of driving Sarah and Mike closer together, just as her father wants. They're also meant to keep other members of the Benoi, who have less than honorable intentions, from forcing her to marry them in an attempt to get access to Sarah's immense powers and all the things that doing so would bring them. And, while Zoahn is among the weakest of his people, he is also the wielder of a Benoi weapon known as The Sword of Stars which, if he were to use it at its full power, would make him even stronger than Sarah. However, he instead uses it for good as he secretly cares for Sarah and wants to see her happy, even though, deep down, despite all he tells her, he's actually not interested in marrying her, as he has his eye on someone else. Even so, he wants the best for Sarah, even though he often doesn't appear to, as he goes about his mission to protect her and bring her and Mike together in ways that seem entirely counter productive to his end goals.