These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Angst? What Angst?: Much of the series is prevalent on the idea that the since this is feudal Japan after the Sengoku Period, violence is something to be taken in strides for the most part. Episode 6 cements this idea when Kawauso is told that he may have to die in order to cement an agreement for his clan. His response? "I've done a lot of things for my clan. But I've never died before."
Also Princess Hitei, who is remarkably unbothered by the death of the only two people she cares about and what she assumes to be her own impending demise.
Base Breaker: Episode 4 is notorious for pissing off large numbers of the fandom.
"Togame" is also touchingly beautiful (and will have you in tears by the end of the anime).
Designated Hero: Played with. Shichika often seems to be a borderline villain, or at least Anti-Hero, and his quest hardly seems to be heroic. Most noticeable so far in the third episode, although his choice of catchphrase certainly doesn't help.
Fetish Fuel: Togame frequently wraps Shichika in her hair as "training" to help him learn to distinguish people. Lampshaded when she accuses him of having a hair fetish.
Togame has her own fetish fuel moments at least every episode.
Freud Was Right: Kanara develops a crush on Togame, because she reminds him of his dead sister.
"Funny Aneurysm" Moment: Togame's Clingy Jealous Girl antics in episode 9 become less funny in light of episode 12's reveal. They show that she really has fallen in love with Shichika — one of the people she has sworn to kill.
Nanami after episode 6. It is shown that she may be the one who wiped out the whole Itezora clan, and most definitely wiped out the whole Shireizan.
Episode 7 confirms the above and adds the conquest of the Seiryouin Goken. And a little scene in which one of the dying guardians of Akutou Bita grabs Nanami's ankle. When she looks at him she doesn't see a person, she just sees a weed that she proceeds to stomp on repeatedly.
When Emonzaemon murders Pengin. He put the gun in his mouth... *shudder*
Viewer Gender Confusion: Rinne, to Perverse Sexual Lust levels. Was once a human, originally a man, now appears in different forms dependent upon the viewer. And the form we see is a half-naked little girl, complete with a strange, cute giggle.
Villain Decay: It gets harder to take the Maniwa ninjas seriously as threats with each new episode. The first one was a skilled assassin who made good use of disguises and trickery and only lost due to bad luck. The second and third are one-shotted by the real antagonists of episodes 2 and 3. Then there's the Insect Squad...poor bastards had the bad luck of going up against Nanami. The Insect Squad even lampshade the Villain Decay; noting that the Maniwa Corp is being seen as the underdogs now.
Averted with their Leader Houou who's making up for their apparent weakness by himself.
However, by the end of episode 10, every single Maniwa Corp head besides Houou and one seriously wounded member is dead.
Lampshaded by Shichika in the final episode, when he kills the Maniwa ninja wielding Soutou Kanazuchi, he says that there wasn't really any Maniwa ninja weaker than that one — if you listen closely, you can hear him laughing as he says it.