I can't tell whether I should be genuinely worried about Thea in Arrow Season 3 or just cautious for the time being. Ever since she left Starling City in the Season 2 finale and eventually returned following her stint in Corto Maltese, she's gotten closer and closer to her real father Malcolm Merlyn (aka the guy who killed a boat load of people in Starling City back in the Season 1 finale, including his own son and Thea's half-brother, Tommy). Sure, Malcolm seems to be a good person to teach Thea self defense and how to find and own her strength, but the guy is bad news. Now Thea is living in a place paid for by the Merlyn estate, which really rubs Oliver the wrong way. Oliver decides to move in with Thea after she offers and agrees that she'll pay for her flat once the club revenue starts coming back in. Oliver is meeting Thea halfway here, but is it really a good idea for him to move in? It might not actually be such a bad decision.
Think about it. Thea has been through so damn much on this show and is actually coming out the other side a stronger, smarter, and a more interesting character because of the evil yet somehow paternal Malcolm Merlyn. It's important for Oliver to try and reconnect with his sister after all the lies and hiding. Besides, isn't it about time that Oliver just come out and admit that he is the Arrow so that Thea can accept it and understand what he's been doing for his family and the city since his return?
Plus, there's the added bonus of Oliver being able to watch over Thea in a space that is meant for both of them, rather than trying to run around looking for her. I mean, he's already got his hands pretty full with trying to keep Diggle out of trouble now that he's a dad, whatever's going on with Olicity these days, and let's not forget about Roy, who eventually will have to tell Oliver that he thinks he killed Sara because of dreams he's been having. Yeah, running around after Thea just isn't in the daily schedule.
Wouldn't it also be extremely cool, if Thea and Oliver can move past the Arrow reveal, for the brother and sister to be able to train together? The thing that Thea seems to appreciate from Malcom is the fact that he's willing to be honest with her — for now. I'm sure Malcolm must have some kind of plan involving getting close to his daughter and manipulating her or their relationship at some point, but for now, he's been nothing but honest. And he's treated her as both a student and a daughter. No matter how much Oliver hates Malcolm, he can't deny that his teaching has made some kind of a positive impact on Thea. But now it's time for Oliver to take over before Malcolm can cause any psychological damage.
If Oliver is willing to be open and honest as well, his relationship with Thea will only grow stronger, even if she does get upset with the reveal at first. I truly believe their relationship can only improve and would actually improve her relationship with Roy in the long run. And if Oliver can take that leap, then hopefully Thea won't retreat into her father's clutches, but will embrace her brother with open arms. And hopefully she won't kick him out.