Eren is with Levi and his squad in the forest on horseback, on there way to the former Survey Corps HQ. On there way there Oruo started to talk to Eren about the place.
Oruo: The former Survey Corps HQ. As an old castle that was renovated to be our base, it definitely looks extravagant. But since it's this far away from the walls and the river, it really wasn't something we needed. It was used back when we were first formed and our spirits were still high. I never imagined we'd be keeping you in that old decoration.
Eren: Ah....
As Eren looks around, he turns to see Levi staring blankly at him. Eren turns back around. Oruo leans in close to Eren.
Oruo: Don't get ahead of yourself, recruit.
Eren: Excuse me?
Oruo: You may be a Titan or whatever, but a pissy brat like you bing under Lance Corporal Levi's watch --
Oruo's horse makes a misstep, causing Oruo to bite his tongue.
Oruo: Urk! Ahh!
Shortly after that the soldiers arrive at the former Survey Corps HQ.
Petra: This is what you get for yapping away on horseback.
Oruo: First impressions are crucial. That recruit was scared stiff.
Petra: I think he was just surprised by how stupid you were.
Oruo: At any rate, everything went as planned.m
Petra: Say, that's now how you usually talk, is it? If... If that's your idea of imitating Lance Corporal Levi, could you seriously stop it?
Then again, it's not like it was similar in any way.
Oruo: Hah... Are you trying to keep me down, Petra? You haven't gone through the proper steps to act as my wife.
Petra: If only you had bit off your tongue and died... You're always bragging about your Titan kills, too.
Oruo: Relax. I bragged for you guys too while I was at it.
Eren: (Thoughts) These people are the Survey Corps' Special Ops Squad, also known as the Levi Squad.
Petra: Sheesh, you're insufferable.
Eren': (Thoughts) Petra Rall. Solo Titan kills: 10. Titan kill assists: 48. Oruo Bozad. Solo Titan kills: 39. Titan kill assists: 9. They're elites beyond a doubt. Ah....
Eld and Gunther walk past.
Eren: (Thoughts) Eld Gin. Solo Titan kills: 14. Titan kill assists: 32. Gunther Shultz. Solo Titan kills: 7. Titan kill assists: 40. They're all elites that were hand-picked by Lance Corporal Levi. And so... if I go berserk, they'll be the ones to kill me.
Gunther: There are weeds everywhere.
This place is a mess.
Eld: It's been a while, after all. The inside is probably covered in dust.
Levi: Now that's a problem we can't overlook.
We'll get to work immediately.
At the former Survey Corps HQ. The soldiers are cleaning. Eren walks into a room where Levi is cleaning.
Eren: The upper floor is clean now. Which of the rooms should I stay in?
Levi: You're to stay in the basement.
Eren: The basement again?
Levi: Obviously. You've yet to gain full control over yourself. If you accidentally transform into a Titan, we can restrain you as long as you're underground. That was one of the conditions given to us in exchange for your custody. It's a rule to be followed.
Eren: Ah...
Levi: I'll take a look upstairs. Eren, you finish up here.
Eren: Understood.
Levi leaves the room. Petra enters.
Petra: I see you're disappointed, Eren.
Eren: Pardon me?
Petra: Oh, I'll be calling you "Eren". Just like Lance Corporal Levi. His word is law here.
Eren: Sure. I don't mind that, but did I really look disappointed?
Petra: It's nothing unusual. He doesn't seem like the completely flawless hero people make him out to be, right? Lance Corporal Levi is actually... surprisingly short, high-strung, violent, and hard to approach.
Eren: No, the thing I was surprised by was how obedient he is to the decisions of the higher-ups.
Petra: Did you believe someone of his strength would have no concern for rank or obedience?
Eren: Yes. I expected him to be somewhat insubordinate.
Petra: I can't say for sure, but he may have been like that before. I heard that before he joined the Survey Corps, he was an infamous rogue in the capital's underground.
Eren: Then what made him change?
Petra: Who knows? I have no idea how it happened, but apparently he was brought to the Survey Corps looking as if he gave in to Commander Erwin.
Eren: Ah... The Commander?
Levi: Hey, Eren!
Levi stands in the doorway. Petra hastily goes back to sweeping.
Eren: Y-Yes?!
Levi: It's far from clean. Do it all over again.
Later in the day, at the present Survey Corps HQ. Mike and Erwin speak as Erwin concocts a plan.
Mike: An expedition to establish a base for a supply chain in thirty days, huh? And you want us to bring the newly graduated recruits along.
Erwin: That's assuming any of them enlist.
Mike: Regardless, I'd have to say this seems too rushed.
Erwin: Eren's current position is only temporary. We need to prove to Central that he's beneficial to mankind as soon as possible.
Otherwise, the Military Police Brigade might interfere again --
Mike: You can't be honest, even with me, Erwin?
Erwin: You're as sharp as ever, Mike.
Mike: I'm still not at your level, though.
Erwin: I'll tell you when the time is right.
At night, at the former Survey Corps HQ. The soldiers are sat down for tea.
Eld: I expect we'll be on standby for a few more days, but I heard there are plans for a large-scale expedition in thirty days. And we'll be joined by the new recruits who graduated recently.
Gunther: Are you serious, Eld? That's rather sudden, especially since the latest Titan attack has undoubtedly taken its toll on them.
Oruo: The brats must've all lost their backbone.
Petra: Is that true, Lance Corporal?
Levi: I'm not in charge of drafting plans. But remember, this is Erwin. I'm sure he's thinking much further ahead than us.
Eld: Well, the situation itself is unusual.
The route we advanced at the cost of countless sacrifices to recapture Maria was erased in an instant. Then suddenly, a completely different hope appeared.
Eren: Ah...!
All the soldiers stare at Eren.
Eren: Ah...
Eld: I still find it hard to believe, but what exactly does it mean to transform into a Titan, Eren?
Eren: My memories from that time aren't clear, but I felt like I had lost myself. I do know it's triggered by self-injury, though. If I take my hand and... (Thoughts) Huh? Wait, why do I know this again? Who knows but I should probably keep the other thing a secret for now.
Levi: You guys are aware, aren't you? The reports cover everything we know now.
Well, I doubt she'll stay put either way.
But she might go too far and end up killing you. Eren.
Eren: Huh? Who's "she"?
Hange: Ah!
From outside the room, Hange makes a loud noise. Petra removes the bar from the door. Hange walks in, holding a hand to her forehead.
Hange: Good evening, members of the Levi Squad. How's it feel living in a castle?
Levi: You're early.
Hange: I just couldn't stay put.
Eren: Squad Leader Hange?
Hange: Sorry for the wait, Eren. I'm in charge of investigating two Titans we captured in the city, and I want your cooperation for tomorrow's experiment. I came to get permission for that.
Eren: An experiment? What would I...
Hange: Well, it's... the most exciting thing ever!
Eren: U-Um... I can't grant you permission myself. I don't have any authority over my decisions.
Hange: Levi, what are Eren's plans for tomorrow?
Levi: Cleaning the garden.
Hange: No problem then! It's decided.
Hange grabs Eren's hand.
Hange: Eren, I look forward to tomorrow.
Eren: R-Right. But what exactly are we going to do?
Hange: Hmm?
Eren: Huh? Uh, well... What do you mean by "experiment" --
Oruo: Hey, stop it. Don't ask.
Hange: Oh, I knew it. You sure looked like you wanted to know. Haha~!
All the soldiers besides Hange and Eren leave the room.
Eren: Ah...
Hange: So you were that curious? Guess I've got no choice. I'll have to tell you then. All about those critters we're keeping.