Ok, so I broke down and started reading a fan-translated version of this manga. In my defence, I guarantee that I will buy a physical copy as soon as it comes out in English. I tried to get volume 1 in Japanese from Amazon Japan but they were sold out. This is one popular manga.
The good news is that I think it will et be licensed internationally. I feel like it almost has to. Sōsō no Frieren did and my preorder is already in. I’m writing this in July but I’m not sure when it will get published. I might have already received my copy of Frieren by then…
So why do I think that Insomniacs will get licensed? Other than the fact that it has been very popular online. Let me tell you about it!

Why I Picked up Insomniacs After School
The title kept coming up when I was researching popular manga that hadn’t yet gotten official translations. And it seems to be pretty popular with Japanese audiences as well. So I got intrigued. I know it’s sort of a romance which I tend to enjoy way more in manga form with certain glaring exceptions.
Official Summary
Nakami is a studious but cranky and antisocial high schooler who gets on his classmates’ nerves. However, his bad attitude comes from the fact that he has a sleeping disorder, and frequently spends nights on end without a single minute of sleep. During the preparations for the school festival, he is begrudgingly sent to the school’s astronomy observatory to gather cardboard boxes, a place which is said to be haunted by the dire happenings of the now defunct Astronomy Club. He finds the isolated place a haven ripe for him to sleep, but while rummaging around, he stumbles upon his classmate Magari Isaki sleeping inside a toppled-over locker.
Isaki, unlike him, is a personable and popular girl at class, but who also hides her own problems with insomnia. Looking for a middle ground, they find that there’s comfort and ease in sleeping together, so they resort to make the observatory their own private cubby to sleep… Have they found the comfort they’re looking for?

My First Impression
Insomnia seems horrible! I’ve never experienced it and even I was getting anxious and sympathetic at the description. I figure anyone who has suffered from a sleeping disorder will relate big time to this manga.
What I liked
I would say chapter 1 was fine but generally standard. It seemed like any number of school-based manga and anime I had read in the past. Obviously the realistic type but otherwise, nothing stood out.
And then slowly, the characters got to me. Or rather they got together. See individually, the characters are pretty good. As in they are very well written and true to life complete characters. Even in volume 1, you can tell there are complex and layered personalities to them. Not just Nakami and Isaki but their friends and teachers as well. However, individually, they also aren’t that striking.
That’s part of the charm really. These characters aren’t special. They’re normal kids. But it’s in their interactions with each other and how the friendships form that the magic really comes through.
In volume 1, there isn’t a hint of romance. Both kids have been dealing with their insomnia on their own. Both hide their condition for similar reasons. They don’t want to be a bother, they don’t want to make their loved ones worry, not being able to sleep just doesn’t seem like an important enough issue to bring it up. So when they meet and discover they are having the same types of experience, it’s a relief to just have someone who understands. That’s all.

They are different people with very different personalities but are united by this unique experience. It’s a classic formula that gets used a lot in fiction. But I’ve never seen insomnia be the uniting factor and it’s surprisingly refreshing and ripe with possibilities.
Both Nanki and Isaki become much more interesting character studies when they are with each other and even the people around them contribute in meaningful ways to building a relationship.
SPOILERS I guess… By the end of volume 1, their little secret room has been discovered by the teachers. They are pretty bad at being sneaky. Thankfully, the understanding school nurse manages to swing things in their favour by suggesting they reinstate the Astronomy club with the two of them as members. As such, they get to keep their little sleep oasis but have to take part in actual club activities in exchange.
It’s a real cute set-up, right?
Any drawbacks?
I don’t really know. The drawbacks I can see are all only possibilities for the future of the series. For instance, the manga is still releasing and I’m not sure how long the premise can hold for. I don’t know if it will devolve into a soap opera once romance storylines hit. Blah blah blah… You can kind of say that for any new manga. There’s always a possibility it will eventually go south.
Conclusion
Fact is, the first volume was well-paced, had surprisingly deep characterization without resorting to any exposition and despite the fact that I was reading a fan translation, was very well written. It’s a strong first volume and I don’t see any reason for the series not to remain delightful!

The art style is lovely and the premise looks really intriguing, I agree it has a high chance of being picked up. Some publishers do monthly reader surveys where they get recommendations on what to license next, so I’ll definitely add this one the next time I fill out one! Great post~
The start is very nice.