YMMV / Under Night In-Birth
Awesome Music: This game has several awesome musics to go. For instance, Hyde's theme Scraper Sky High, Seth's theme Monochrome Memory, Orie's theme Purity And Strictly, Sion's theme Blood Drain -Again-.
The recent update gave us a theme for Hyde vs. Seth matches: Mutual Situation, a mash-up of their respective themes.
Crack Ship: Merkava/Vatista is oddly popular despite their interactions in their arcade ladders being less than friendly.
Complacent Gaming Syndrome: A LOT of people have been using Phonon nowadays ever since the release of Exe: Late[st].
Ensemble Darkhorse: With how much fan-art Vatista gets, you'd swear she's far more relevant to the plot than she actually is. In general, she's loved for having a cute design along with having one of the most unique movesets in the game.
note Not to be outdone, Merkava is also quite popular.
Fan-Preferred Couple: Alongside the above Merkava/Vatista, Hyde/Vatista is also popular, thanks to their interactions in the latter's arcade scenario.
Memetic Mutation: Nobody wears panties. This video is a bit of proof.
Moe: A good majority of the female cast are this, but Vatista and Yuzuriha are notable examples.
Most Annoying Sound: Of course, Hilda with her Noblewoman's Laugh.
The Scrappy: Nanase is commonly hated for being an Ungrateful Bastard towards Hyde, while looking and acting like a stereotypical Tsundere in a game otherwise clean of anime cliches. People also tend to find her voice annoying.
Tier-Induced Scrappy: Quite a few...
Gordeau, due to reaching damn near Game Breaker status via the reach on his attacks.
Chaos is often on the low-end of the spectrum, due to how little he has in the way of reversals and being unable to command Azhi Dahaka while under pressure himself.
Waldstein is a Grappler character that is generally held to be the second-best character in the game. You Can Panic Now.
Merkava is usually part of the trinity of the best characters in the game, alongside Gordeau and Waldstein, but his darkhorse status protects him from fan backlash a bit.
Akatsuki, due to his hindered physical range on his normals which prevent him from playing a decent footsies game compared to everyone else. This was before most of his buffs in Exe: Late[st].
Phonon, ever since Exe: Late[st], where she's used very frequently due to her long range and solid hit-confirms.