adachi is one of my favorite characters from anything ever! i really like villains who are unpleasant as well as (or instead of) "evil" in that abstract cartoon-baddie sense. i feel like fiction so often has a strange distinction between "bad" and "evil", where "evil" usually amounts to wearing all black and wanting to fight good guys and is more like a job or narrative role than something about their moral character. jrpgs in particular tend to have pretty over-the-top villains with a lot of high drama and flying around wearing a cool outfit. (i like those guys, too).
persona 4 is generally a very pleasant and optimistic game. it's about acceptance and friendship, about being true to yourself, about finding the charm and joy in situations where other people find it difficult. inaba is an ordinary place, a boring place, a flawed and depressing place with nothing especially good about it. but as you the player guide yu narukami around and learn more about it, you find that nothing in the world is really all that bad. there is always something fun, something charming, something to care about, if you have the time and patience to look for it under the surface. this world is, at its core, beautiful - if you just reach out, if you put in the work, if you accept the ugliness and let it be what it is...
some people are just bad.
some people, when you reach out, will wring you dry and leave you empty. some people will hurt you on purpose, not for any particular reason at all besides the opportunity presenting itself. being open and generous and interested can be a bad thing. you can and probably will get hurt, because that's a part of life. you will meet so many wonderful and interesting and charming people, and you will also meet people who are awful.
adachi is just bad. he has no tragic backstory, no motivation, no plan, no cause, no extenuating circumstances. he's cruel, he's lazy, he's manipulative, he lies all the time for no reason, he complains constantly, he's selfish and pessimistic and rude. he thinks everyone else is just as bad as he is; after all, everyone has the capacity for cruelty, everyone lies sometimes, everyone hurts each other. everything is pointless and boring to him. he is existentially unsatisfied, totally empty inside. he does not enjoy anything, he does not like anyone, he has no hobbies or friends or even any personal effects. he coasts through life barely interacting with anything.
yu tries very hard to connect with adachi. he wants adachi to be good deep down - he keeps digging and digging, looking desperately for signs that adachi really is good, kind, fun to be around, but there's nothing there. the harder he tries the more danger he puts himself in. lying to yourself, refusing to face the facts, is bad for you and bad for everyone around you, after all...
anyway, yeah. adachi is bad in the way that people are bad. he sexually harasses mayumi and saki, and when they don't behave the way he wants them to he kills them. he became a cop so he could feel powerful, and he uses his position of power to hurt people. that's a real kind of guy! a real thing that happens all the time! it's awful and it's totally mundane.
for me that makes him a really compelling villain! he's exactly the sort of person you don't want to be given magical powers. he's a great foil for the protagonists and forces them to confront unpleasant things about the world and figure out how they feel about it and how they're going to respond. sometimes there isn't a good answer or a real solution, and sometimes you have to really think about what you believe the good and right thing to do is. that's something the kids in persona 4 have to decide: should we bring him to the police, who we know are corrupt and incompetent and can never actually prove he did anything wrong? what else can we do? should we kill him? is that really ever the "right" thing to do? the drama! the conflict! what fun!
i love unresolved and unresolvable tension, i love no-win situations, i love for characters to be faced with problems they cannot solve and things and people that make them really deeply upset. that's very fun for me.
you also cannot overestimate the powerful horny factor that comes from a horrible guy who is canonically a sadist who enjoys tormenting people. i really like adachi's dynamic with the protagonist; "desperate & hopelessly in love & eager to please" plus "hateful sadist who enjoys taking advantage of people" is a very potent combination for shipping.
