For a webcomic described by the author herself as a "Slice of Life-Romantic Comedy," Sakana has a surprising amount of somber, hard to read, or otherwise just downright depressing moments, usually either by means of Backstory Horror or Adult Fear. Or both.
- Genji quietly apologizing to Taro after the latter has already taken off in frustration, very clearly fed up with the former for trying once again to sponge some money off of him and Ren. It doesn't help his financial situation much, but it at least makes it clear to the audience that on some level, Genji really does wish things had turned out differently, and that he could interact with his family at least a little more smoothly.
- There's some indication as early as page 24 that something happened to the Sakana brothers' parents, and whatever it was, they don't seem to be entirely over it. Even Taro, who's kind of universally accepted as being the tougher of the two, seems to freeze up when he finds Jiro asleep while holding a framed photo of them, and even more so when he tries to talk to it himself.
- In that same vein, after Jiro learns his date, "Cash Register Girl," was actually Chie Yamamoto, the terror of his preschool years, (and that Taro, Taisei, Angry Lady/Mori, and Yuudai were spying on them the whole time) they decide to go to a park to get away from the unfolding chaos. She tries to apologize for everything that happened back then, as she believes that it's what made him leave the school... until he cuts her off, and explains what actually caused him to leave. Everything just gets... quiet, and while Jiro's not in tears about it, you can tell that it's still something that's deeply affected him and his brother.
- As adorable as Taisei almost immediately warming up to Yuudai is, there's just something that's kinda disheartening and more than a bit troubling about the fact that Yuudai can't seem to accept that someone would be genuinely nice to him. When he and Taisei get around to talking a little more, he ends up snapping and accusing the other of making fun of him. Jesus, someone give that guy a hug.
- And then we find out why he's like that. Yuudai's increasingly short temper, his hateful mistrust of everything around him, and his aversion to physical contact suddenly become a lot less funny when you find out that they're most likely the results of being in an emotionally (and at least during one instance, physically) abusive relationship for five years. And he only managed to leave after his then-partner Arata temporarily disfigured his face with a glass bottle. Yeesh.
- Chapter 16 in general is hard to read, given that it's an incredibly tense chapter about Arata cornering Yuudai when the two of them are finally alone, verbally curb-stomping him, and Yuudai being so unenthused at the prospect of his former abuser being in his apartment that he ends up taking to the streets - although that last part is actually Played for Laughs thanks to Yuudai being so hammy about it up until his last line in the entire chapter:Yuudai: This is a terrible idea.
- Their entire exchange at the cafe is difficult to sit through, especially if you're one of the many readers who was already attached to Yuudai by this point, but this line hits especially hard. Arata even tries to backpedal once he realizes it may have come out harsher than he wanted it to:Arata: You don't have to change for me. I already like you. And really... I don't wanna be mean, but... let's be honest. I'm the only one who can put up with you anyway.
- Their entire exchange at the cafe is difficult to sit through, especially if you're one of the many readers who was already attached to Yuudai by this point, but this line hits especially hard. Arata even tries to backpedal once he realizes it may have come out harsher than he wanted it to: