Anyone ever watch a show specifically for one character? Everyone has their own reason for watching something no matter how odd or specific no matter how the thing they decide to watch looks like itll turn out. Sometimes they just like the vibe and wanna experience that all the way. Sometimes they just really like a song or one of their favorite artists is doing the OP or ED. Sometimes clips have convinced you that a show has baller fights or in the case of this show clips have demonstrated one character who sells the anime alone. Its not the sister. In fact lets get this out of the way now the titular onehitkill sister Maya is gonna be a make or break aspect of the show as other aspects and faults will often be supported or hindered by the experience of watching a brocon constantly smother and even sexually harass her little brother. Thats certainly a fetish some people are down for but perhaps the main reason this show is even worsereceived than its contemporaries this season many of which seem significantly more poorlyproduced and include fucking Smartphone S2 is the fact that Maya is insufferable most of the time. They can range from kind of annoying to disturbing and even manipulative though of course that means were supposed to find it gutbusting or even nutbusting. There are some decent bonding moments and snippets of conflict between her and actual MC Asahi. The weaklings desire for independence and his need to grow stronger both for his own sense of selfimprovement and his own sake given the dangerous world is combined with how adventurers caught falsifying their rank are dealt with is an alright source of character development. Asahis a bumbling little squirt annoyed at how unlike basically every other isekai MC this season alone his base stats are equivalent to how original worlds self without any crazy OP powers therefore making it harder to do anything including evading Mayas advances until episode 4. Still slowly but surely he trains which we should see a bit more of he acquires powers and improves his evasion and techniques to the point of being able to make up for his weaknesses. He may not recognize it perhaps many viewers dont either but Maya does which helps elevate both characters up a little while solidifying perhaps more character development than some isekai consumers and haters are used to from one of these. She herself has some surprising moments of actually sincerely looking out for him in the shadows even if its always preceded by or followed up by a gaudy sexual or romantic advance in the same episode. Otherwise this show has a comfortable enough vibe. Tensions are minimal but they get played upon to at least a perfunctory degree and there is some decent comedy to be had with Asahis bullshitting or some of the character dynamics. The latter aspect is mainly found in the borderline sitcom arch nemesis who carries the show on its back Kilmaria. Shes a blood knight demon among the demon lords top guys and after being saved by Asahi despite tryna fight him on the grounds of his reputation she quickly develops her own dynamics with the main duo evolving them over time. She goes from casually hanging out with and mildly looking down on Asahi as a sort of little brother to someone who cares about him more and more with each passing adventure. She goes from seeing Maya as this insufferable and hypocritical rival to one she eventually starts getting along with and making fun of. Perhaps her best showing is in episode 5 where in a human disguise she starts being excited by all the little things in a human society like horses bridges and the weak masses before rubbing Asahi the wrong way about how weak and inconvenient being a human must be. Of course the show never hard commits to any conflicts it dredges up save for one example that introduces one of Asahis eventual harem members he builds up over time but the inklings are welcome enough and some of them get just enough exploration without making the show actively need to take itself seriously. The other characters in this show arefine? Sophie the healer is kind of annoying as an overzealous Asahiworshiper Tanyas the questgiver and total fangirl who does get an ok story with her little brother who also looks up to Asahi. Glorias a fun meathead girl who eventually swaps out her suspicions towards Asahi for a dorkaholic romantic interest in him that her servant Kuon attempts to wingman. Shes probably the second or third most fun girl in the show. Some of the other side characters like the eventually washedup adventurer Siegfriend are amusing as well especially when the source of his partys humiliating downfall unknowingly greets him again. The cast is honestly on the upper half of isekai rosters in all honesty and you bet that Kilmaria makes at least some of them bounce off her. Even without her elevating everything for most of the show eventually enough of them come into their own to help make the cast surprisingly decent on the whole. Theyre actually kinda funny with nearly every episode having at least one funny moment and a few bits actually being kinda hilarious. Its also oddly nice how much they back each other up defending each others character in the face of whoevers goading intimidating or otherwise confronting them. It adds a sense of camaraderie to everyone that cant quite be found in a lot of this shows contemporaries even Slime and that series actively has a community being built from the ground up. The ways everyone comes together in the finale are rather fun and rewarding to see as a result of everything. Another aspect of the show thats better than it realistically should be is the visuals. For the most part it looks pretty subpar. Its Gekkous first release as a studio and a directorial debut by Hiroaki Takagi and it could be worse on either front. Sometimes it absolutely is. The shows production is so jittery that while 6095 of the time it looks about what youd expect from your average seasonal sometimes itll either dip into astonishingly terrible territory or bust out a couple of surprisingly decent cuts. There are plenty of animation errors even outside of the freakish drops in quality like with the dragon in Kilmarias Chinese dress disappearing a lot. The action rarely gets past just ok even when we get an oddly fine burst of sakuga. The volleyball scene in the beach episode episode 11 is an atrocious minute of slideshows and the fanservice can range from perfunctory to downright crudely drawn so just be glad this isnt classified as an ecchi because as mediocre it is as an action show it would fare even worse as an ecchi title. The outlines tend to not stick out but sometimes the show thickens them as part of a gag of for more climactic closeups. The show also does play around with aspect ratios every now and then like letterboxing in the first half of episode 1 and 4:3 in the flashback sequence that kicks off episode 7. The characters also deform into charmingly drawn chibis for a bunch of silly gags and spats usually Maya and Kilmaria who also carry the brunt of the relatively amusing facial expressions. They do try to spice things up occasionally and that is welcome. It honestly feels like theres enough potential in the visuals that if it were made to simmer for another 3 months the end result could have wound up being legitimately above average for a seasonal let alone an isekai. Unfortunately thats not the case. A more consistently mediocre aspect of the series is its music. The ED Mukyuu Platonic by VALIS is an oddly decent electropop song with hints of melancholy in it which makes it better than both OPs. The music is also fairly forgettable outside of Mayas theme and Kilmarias theme which get spammed basically every episode. There is an occasionally decent track once in a while like when Kilmaria tries to get Asahi to abandon Maya and become a demon and theres an alright insert in episode 11 that gives the siblings some time alone to discuss how far theyve come in a mostly pleasant scene. However that doesnt really elevate the music much as its still incredibly whatever across the board. One Turn Kill Neesan can be a pleasant goofy ride that revels in its own absurdity while boasting more character development and fun dynamics than one might expect. Its also got brocon shit that will either elevate the experience for you if youre into it or make the show a trudge to sit through for the good bits if you arent. Its very annoying and kind of embarrassing but it is kinda cute and fun especially whenever characters are being dorks or having each others back. Still theres enough here to elevate the show well above the likes of Smartphone Master of Ragnarok Arifureta or probably half of the isekai youre watching this season because Kamikatsu looks like it was edited by YouTubers derogatory and animated by an outsourced studio in another country. In terms of an isekai you can just sit back and watch you can do a lot worse. Name another isekai that has Kilmaria in it. Also this is a nonSunrise show nonmecha seasonal at that which features a relatively acceptable mecha transformation sequence...in 2D. Wasted as it is on a lastminute outing and oneshot that fact alone is borderline commendable for one of these especially considering its an isekai.