Blue Box is a pretty good anime. The production quality is solid across the board. The animation is clean, the tone is consistent, and the badminton scenes are intense when they need to be. You can really feel the effort and pressure in those moments. Though, badminton feels more like a backdrop than a driving force in the story. The show isn’t really structured around the sport itself. There aren’t deep tournament arcs or rivalries; but rather, the matches and training sessions tend to reflect the emotional states of the characters, especially Taiki. It’s not that every game exists to lead into romance, but the sport is clearly tied to the characters’ inner lives more than it is to a competitive arc. This isn't a sports-romance anime, it's a romance anime with sports. While this may not seem like a problem to some, it felt like a missed opportunity to me.

Hina stands out as one of the most compelling characters. She’s likable, forward, and emotionally honest in a way that feels refreshing in a genre full of “maybe if I stare long enough, they’ll know I love them.”She makes her feelings known, takes the risk, and faces the fallout, all with a level of maturity that makes her easy to root for. You see her grow and process what she’s going through, which gives her character arc real weight.

Chinatsu is... a frustrating character. The biggest issue is the way she constantly sends mixed signals to Taiki. She’ll act emotionally close or imply there’s something between them, then back off completely with a vague excuse about not being able to think about romance. The push-pull dynamic feels less like natural emotional complexity and more like intentional baiting; like she wants to keep Taiki close just enough without ever confronting how she actually feels. And because the show rarely lets us see her inner thoughts, it’s hard to empathize with her. Her character remains stuck, not developing, and it makes her role in the story feel passive and emotionally exhausting to watch.

The romance is incredibly slow, and not in a satisfying slow-burn way. It’s more like emotional buffering. Chinatsu spends the entire show hovering in romantic neutral. Meanwhile, Hina makes her move, faces reality, and develops. Watching the show feels like rooting for a character the story has no plans of rewarding, while the actual “main couple” is stuck in an awkward holding pattern.

Taiki himself is a solid protagonist. He’s focused, kind, emotionally aware and hardworking. It’s respectable, but narratively kind of flat. He starts off as someone who works hard and supports the people around him, and he remains that way. He reacts to situations more than he grows from them. Compared to Hina, who gets a full emotional arc, Taiki feels relatively static.

Side characters help flesh out the world and bring in different perspectives. Ayame is a great example of this. She doesn’t always understand what’s going on and sometimes says the wrong thing, but that’s what makes her feel real (and annoying tbh). She’s not conveniently insightful like some supporting characters in romance stories. She grows in a short amount of time and offers a grounded, human reaction to everything Hina’s going through. Karen serves as a contrast to Chinatsu and helps show herself and the audience sides of Chinatsu that wouldn’t be seen otherwise. Kengo is more of a background presence, a reliable upperclassman that adds texture to the sports side of the story.

Kyo, on the other hand, feels more like a device than a person. He always seems to know exactly what’s going on... even when he literally hasn’t been part of the scenes that would give him that context. He's like an all knowing god who knows everyone’s location, feelings, and ETA to confession. His role is mostly to push characters in the right direction and say things the audience is already thinking. It makes him feel less like a character and more like a tool for the writer to move things forward when needed.

The show does rely heavily on standard romance tropes: the love triangle, the childhood friend who loses, the emotionally distant main love interest, the same house setup. It doesn’t do anything especially new with these ideas, just keeps them the same way we always see them. That’s not necessarily a problem, but it does mean the story can feel predictable if you’ve seen similar series.

Still, there’s a lot to like. The emotional tone is consistent, the quiet moments are often effective, the badminton is well-animated and enjoyable, and certain scenes, especially involving Hina, hit surprisingly hard. I enjoyed it, even if it was occasionally frustrating. It’s one of those stories where I find myself more invested in the side characters and emotional fallout than the main relationship, but is still an incredibly solid show.