The dungeon is in Korea, but as an esper with a pretty specialised power niche Haru is used to occasionally having to go international for these dungeons, and the fact that he already speaks Korean is definitely a bonus. The espers he's going to be working with are all in Quasar Guild, which is the largest one in Korea and which has just recently acquired a very powerful teleportation esper, one whose power can be stored in batteries Quasar also happened to already have in its possession, so they're covering the teleportation cost for Haru to get there.
"No you. You're going to take all the steam out of my rant. Are you sure you want the rant and not to just be cute at each other."
"...I know you too well to think that the alternative would be you doing anything like 'bottling it up' but I feel like there might be some—catharsis—in it? But maybe I'm wrong about what you... mean by it."
"I think the upside potential is something along the lines of - you really could not have picked a more horrifying thing to be going around doing, for me personally, and maybe it is valuable to have that fully communicated both for squishy mutual understanding reasons and also for Project Cut It Out Forever? And also I thought of a very mildly amusing analogy, but it's really not one of my best. It is totally fine if you don't wanna hear it in any more detail than 'that was horrifying, cut it out forever'."
"On the one hand this could be inviting—stress and emotional harm—that might not accomplish anything, especially given the—distance I want to put between me and those choices. In the sense of—I haven't done it in weeks and there's a chance there's some fragility in my sense of accomplishment which could be disrupted by feeling like, if that clean break wasn't enough, nothing will ever be."
"And on the other, I—want to know you better than anyone else. I want to know you best. So if there's anything you could say that I couldn't predict in—sufficient detail—that means there are things there about you that I don't know. And you don't—owe me, knowing every detail of your life, just because I want to. But I want to.
"Plus, there's a part of me that I haven't entirely, ah, 'notebooked' away, that is still waiting for the other shoe to drop because of how calm and collected you've been about the whole thing so far. That part of me is sure that you're going to be holding something over me, until it can see that something exist and go away. It's the same part of me that wanted you to be completely unfiltered with me earlier, that wants to know—everything, the good and the bad and the ugly, to know what works and what's broken, so that it knows where to step confidently and where to tread carefully."
"Wow, good job Kang Jaeha those were lots of words that communicated things rather than sitting on your feelings, right there, get a cookie." He pats his own head.
"...wow, you're doing amazing, I have never seen my notebook thing work for anybody else." Haru also pats him on the head. "Would it split the difference usefully if I complained about, like, mind control science fiction plots? So that you hear more about my feelings on the topic without it being about you."
"Hmm, it'd—plausibly? I... Give me a moment." He closes his eyes, but it turns out to be just a moment, because this was one of the things that was looming largest on his mind when he decided to start writing down everything he'd been feeling and it's fresh and ready to be put to more words. "The thing about—wanting the other shoe to drop—I know I said I haven't gotten rid of it yet but I don't actually know that I can get rid of it at all, is the thing? Or—probably I'll be able to, eventually, but—given how much it seems like that desire has driven such a big part of why I've used my powers in the past, leaving it to simmer afraid in the background could be—bad—but then again it could be good to just stop feeding it altogether.
"I think if—you did the thing about the plots, but then also told me more about—hmm. I don't know. I don't know what would be sufficient, for that part of me to truly believe that it's safe."
"We can start with that, and see what still feels missing, if anything? I digest most of my science fiction these days in the form of telling Cricket what shows have been recommended to me and having him summarize, but probably if it's going to feel very vulnerable you wouldn't want him in the room, I can dig up a short story or something that I'll have time to read or that you could read to me."
"I would still love to turn Cricket's opinion of me around and get him to like me but it seems like a hopeless prospect at this point, and this might hinder that project rather than help, so plausibly including him would not be ideal, yeah."
Haru leans his head on Jaeha's shoulder. "I take enormous satisfaction in Cricket liking me but not in a way where I think it reflects poorly on anyone for him not to like them." Om nom tteobokki. "Mm, this is good."
"- you know what would work would be Harry Potter," says Haru, after he has located a literal cookie to present to Jaeha. "It's not short but there's several kinds of mind control in it and I remember it well enough for all that I last read the whole thing through when I was twelve."
He got a LITERAL COOKIE from his Haru it doesn't matter that it's a cookie from his own damn kitchen he is being materially rewarded for being good at communication and he is going to do the most creating positive incentives in his head about this he can.
"Same. Sure, let's hear it."
Haru has OPINIONS about mind control in Harry Potter. The casual references to love potions - the author decided to heavily imply that being conceived under the influence is what made Voldemort so evil but has nothing but amusement in her heart about schoolchildren sneaking doses to other schoolchildren, or the less overtly unpleasant of the Potions teachers possessing Amortentia for some reason and displaying it in the school when the school's security measures for in-universe-taken-very-seriously items of value can and have been bypassed by eleven-year-olds.
The Obliviation, on so thin an excuse for having a masquerade that it would have been better not to bother to try, and where they don't Obliviate it's because they can instead coerce and intimidate, as with Harry's relatives; at no point does any wizard ever try to convince anyone they could instead casually overpower or extort. Particularly egregious in the case of Hermione's parents, who by rights ought to have been convinceable and whose ignorance wasn't even legally mandated, and who instead are replaced with versions of themselves who yearn to move to Australia and don't have a daughter, which, if she'd died, would have completely denied them the opportunity to ever remember and grieve their child - she doesn't even give her allies a way to look them up afterwards for the case where the good guys win their conflict but she herself doesn't happen to survive - and given that she didn't die and one might generously presume she put them right later (it doesn't say), presumably created some dreadful emotional fallout, about the resolution of which absolutely nothing is said.
Comparatively speaking Haru is not that fussed about the Imperius Curse. That is, it's obviously an atrocity, but it's not worse than a memory charm. It commandeers the self, but it doesn't undermine it, though prolonged use obviously has plenty of opportunity to undermine someone's relationships and personal boundaries and life plans. A student learning to throw the curse off who jumps onto the desk when so commanded can still come to terms with this eventuality on their own time without any gaps in their ability to do so. And the exercise seemed to have more of the (ostensibly) intended effect than the Occlumency lessons, which -
Legilimency! Fucking everywhere Legilimency! Good guys doing it, bad guys doing it, everyone acting like it's a neutral skill! If Haru lived in this setting he would fucking LEARN the Occlumency, even if no evil wizards seemed to be specifically after him and even, perhaps especially, if he hated his poorly-thought-out assigned teacher who kept trying to read his mind as an ostensible form of education; it doesn't even sound hard, though, like, obviously whether something that doesn't exist sounds hard to someone reading a book about it is not necessarily indicative.
...okay no that all just sounded 1. correct and 2. incredibly endearing. Kang Jaeha is too much of a 25-year-old Korean man to properly swing his legs back and forth like an American teenage schoolgirl from an 80s movie watching her crush speak but that's very much the emotional tone, here, he's finding it delightful to hear Haru be so opinionated about all of this.
He really, really likes Haru.
In English or in Korean he's not going to ask Haru to confess, that wouldn't be cool.
Time to be serious again, though. "I'm glad you have the power you do. As you say, a lot of people are a lot more chill about this kind of thing at least in fiction than they probably ought to be, but I'm glad that you can block it altogether.
"I'm not particularly surprised or dismayed by any of this and I'm not missing the obvious parallels, either. I do agree with every single thing you said, here."
"- no, I've been very deliberately saying 'horrified' and not 'angry', it's not - positioned in a way where I'd be angry about it? I probably would be if you'd done anything to Cricket or my parents."
"Are you horrified at—by—me, personally? As opposed to—I'm not sure what, really. 'My choices, disembodied and devoid of cause' is where I wish that would be, but..."