I like this series...so much.
There's a very brief and quickly resolved blip of jealousy again at the beginning, where Kaburagi clocks Kasai's growing crush on Onoe and puts a stop to it by telling him that the two of them are together (something that Kasai, as a stakeout specialist, had pretty much already figured out). The surprising part was that Onoe really didn't freak out about the secret being spilled - but while they're not being open about their relationship, they're not trying all that hard to hide it, either. They're comfortable and happy with each other, and it's mostly just not anyone else's business at this point.
The storyline mainly centers around someone who does have quite a lot to hide, and we dig once again into the really dirty parts of what their jobs entail. Onoe's still not particularly happy about how much time they spend prying into people's private lives, and while he denies Kaburagi's astute observation that he's feeling sympathy by putting himself in their shoes, that's kinda how the rest of the plot unfolds.
Onoe ends up befriending and getting attached to an older (40 year old) actor who's very charming and tells Onoe exactly what he wants to hear. It turns out, of course, that he's doing something a whole lot worse than just sleeping with a younger actress, and the rest of the volume is about digging up that story, deciding whether to pursue it, and dealing with the consequences.
I really, really like that yet again the drama and the conflict is an external thing that Onoe and Kaburagi deal with together. When things get bad, Kaburagi's the person Onoe can turn to - just needing a hug, which comes as a very satisfying full page panel once they get home.
"Home," by the way, meaning Onoe's apartment, which Kaburagi has unofficially semi moved into.
While their idea of getting a new, bigger place together has been put on hold at the end of this volume, I hope that's what comes in volume 5. After all, if their main concern is that their bosses will think it's weird that they share an address...I think that ship's pretty much already sailed. Everyone knows they're close and sees them leaving work together and night and arriving together in the mornings, so it'd be a big surprise if there's anyone left to be surprised. And yeah, of course I'd love to see some additional domesticity.
Love love love this sadly rare genre of an established relationship. I wish I could find more series like this, but I'm glad this one has enough for me to indulge in.