meh

My main thing is that they definitely met in a goth/industrial crossover club. Higuchi I headcanon as a rivethead. I've decided he's really into Slick Idiot and Lords of Acid (a friend of mine introduced me to them). Namikawa is definitely a goth. Like, undoubtedly. He oozes "you can't sit with us" goth elitist attitude. Nothing but contempt for the world and a sense of betterment over "appreciating the classics". He's a trad goth kind of guy: SoM and Christian Death, but I think he'd also like a lot of Japanese bands like Phaidia, Auto-Mod and Kokushoku Elegy. He doesn't like Sadie Sads because they're too weird and he doesn't like 80s Buck-Tick because they're "not goth enough". A bit of a tangent (lol) but basically Namikawa's morbid curiosity ended up in him dating Higuchi,

Along a similar train of thought, they hate each other's music taste. Higuchi thinks Namikawa's music is "pretentious as hell" and Namikawa thinks Higuchi has the music taste of a teenage boy. They frequently argue about music taste and Higuchi laughs at Namikawa for saying every goth band that has a harder sound is probably industrial,

Their relationship isn't 100% healthy. They do fight a lot (usually over nothing). Their arguments are extremely petty, but occasionally Higuchi feels a little sidelined by Namikawa. Namikawa has a habit of treating him like an embarrassment (you know those "I can't take you anywhere!" sorts of people). This obviously, as it would for anyone, makes him feel extremely insecure, which isn't ideal since he already fucking is. Higuchi had major self-esteem issues before their relationship (he has his whole life) and Namikawa only exacerbates it. I will say that I don't think Namikawa does it on purpose, and in a way that makes it worse. He doesn't think about how his nature affects his partner's self esteem because to him, insecurity is entirely foreign. He's never had to worry about looks, intelligence or popularity the way Higuchi obsessively does because he's treated 10x better by literally everyone. Namikawa's behaviour isn't intentionally malicious, but it has a negative effect nonetheless,

Higuchi and Namikawa aren't publicly involved with each other (obviously Japan in 2003 isn't going to be a bastion of LGBT rights, and people don't really talk about relationships anyway) but they do have each other's backs in their own weird ways. Higuchi will talk insane shit about Namikawa both to his face and behind his back, but gets extremely pissed off if anyone else does it. Kind of like how you're allowed to talk shit about your sibling but nobody else has the pass. This massively confuses the other Yotsus and the more astute ones of them (anyone but Takahashi) suspect that they're undoubtedly dating. Namikawa is more subtle. He doesn't necessarily chastise people for saying anything bad about Higuchi, and he's definitely the first to tell Higuchi when he's being an idiot, but he does make sure to change the subject so that the other person can't continue slagging him off.

Namikawa is the one that remembers important dates (and general to-dos). He's the one that drops the "it's our anniversary soon" and Higuchi is the one that grits his teeth and thinks "shit, I completely forgot". Namikawa books their dates because betting on Higuchi remembering to do it will give you a permanent losing streak. One Higuchi headcanon I have is that he has pretty bad ADHD, and was treated like a problem child his whole life, but wasn't taught how to deal with his disorder. This manifests itself as him forgetting to do a lot, alongside general impulsive behaviour. The only time Higuchi will actually organise a date is on a whim, and he'll tell Namikawa last minute (much to his dismay). Just another example of the shitty things they do to each other (they're such a perfect match).

In short, Higuchi and Namikawa deserve each other and nobody else because subjecting a third person to either one of them would be exceedingly cruel and a violation of their peace of mind.