* AdaptationDisplacement: Chances are, if you know about ''One'', it's because its characters are in ''VideoGame/EternalFighterZero''.
* BaseBreakingCharacter: Since the 2023 remake came out, fans have been split on whether Kouhei is an interesting, compelling protagonist or a complete {{Jerkass}} whose actions towards his love interests are [[UnintentionallyUnsympathetic too mean-spirited and cruel to make him come anywhere close to being sympathetic or likeable in any way]], with many being completely repulsed by how he tried to subject Mizuka to a NearRapeExperience in her route.
* CultClassic: Considered a classic by those who know it, the two biggest reasons being it is the predecessor of ''Creator/KeyVisualArts', and that it was a pioneering game in the Nakige genre.
* FanworkOnlyFans: DoujinSoft games with ''One'''s characters, most notably ''VideoGame/EternalFighterZero'', tend to be played far more than the visual novel itself is or the [=OVAs=] are watched.
* HarsherInHindsight: Inverted in how Kouhei first meets Misaki and decides to not say anything. Since Misaki is blind, she keeps calling hello, and when no one answers, she becomes afraid they fell unconscious.
* JustHereForGodzilla: One of the only reasons to see the [=OVAs=] or play this visual novel is because ''One'''s characters are in ''VideoGame/EternalFighterZero''.
* MainstreamObscurity: Due to ''One'''s characters appearing in ''VideoGame/EternalFighterZero'', many have heard of ''One'', but very few have actually played this visual novel. It doesn't help that the non-hentai OVA is universally despised.
* TearJerker: Most of the routes. Fans, however, tend to agree that Misaki had the most depressing one.
* TheyChangedItNowItSucks: Many fans consider the non-hentai OVA to be guilty of this. It was only loosely based on the game and the characters get changed. The hentai OVA however stick very close to the original story.
* UncertainAudience: The OVA adaptations have no idea who they want to appeal to. The story and characters are unexplained to those who haven't played the visual novel, and almost none of the iconic scenes of any of the character routes are shown, alienating those who have played the visual novel. In fact, the events even directly contradict the canon of the visual novel.
* TheWoobie:
** Mio, especially during her route.
** Shiina to a lesser extent.