* [[BannedInChina Banned In New Zealand]]: According to {{the other Wiki}}, the anime adaptation was refused classification in New Zealand, effectively banning it there. On the other hand, both of the dubbed seasons are completely available in Australia. All three seasons have been recently banned in China as well.
* {{Expy}}: Issei's design is actually based on [[Anime/SCRYed Kazuma]] because the author is a fan of the series.
* FlashbackWithTheOtherDarrin: For the dub, when they go back to moments of the first two seasons where Issei talks, this happens of course. In the case of his gate-crashing Riser's party, they even put in a new line to go with the new voice actor.
* FanNickname:
** Hypnobutt - Koneko [[MaleGaze swaying her butt on the screen in the ending]]
** Weapon [[{{Netorare}} NTR]] - [[spoiler: for Issei and Kiba ''hijacking'' both True Longinus and ''all'' of Siegfried's swords respectively.]]
** GAR-sper - In some circles, Gasper after his awesome moment in Volume 10.
** [[Manga/{{Bleach}} Kenpachi dragon]] - Grendel is called this in the {{Imageboard}}s thanks to his BloodKnight attitude while fighting Issei.
** Dragon swag - What fans refer to when Issei attracts someone's attention.
** Dickora - for Diodora, which further cements his status as TheScrappy.
* IKnewIt: Some people got it correct when [[spoiler:they thought that Great Red was going to help out both Issei and Ophis. ''No one'', however, thought that Great Red has a {{Delinquent}} personality.]]
* NamesTheSame: Sister Creator/AsiaArgento
* NamesToKnowInAnime:
** YuukiKaji is Issei Hyodo, [[{{Irony}} ironically]] [[PlayingAgainstType making him an anti]] [[Anime/GuiltyCrown Shuu]]. Oh, and [[Manga/AttackOnTitan he fights titans in another dimension.]]
** Creator/YokoHikasa is Rias Gremory [[{{Irony}} ironically]] the one [[LightNovel/KoreWaZombieDesuKa reviving the Dying protagonist]].
** Creator/ShizukaIto is Akeno Himejima, ironically becoming a half-devil after [[Manga/DGrayMan undertaking a career as exorcist.]]
** Creator/KenjiNojima is Yuto Kiba, [[{{Irony}} ironically]] being the calm person compared to say, [[VideoGame/TheLastRemnant Rush Sykes]].
** Creator/AyanaTaketatsu is Koneko Toujou (and [[Manga/KOn she keeps the cat motif]], too!)
** AzumiAsakura is Asia Argento, [[{{Irony}} ironically]] [[VideoGame/TheIdolmaster not shy around guys.]]
** Creator/HitomiNabatame is Raynare
** Creator/TakehitoKoyasu is Riser Phenex
** Creator/FumihikoTachiki is Red Dragon Emperor Ddraig, making him the real [[Manga/{{Bleach}} Kenpachi]] dragon.
** Creator/JunichiSuwabe is Sirzechs Lucifer. [[VisualNovel/FateStayNight GARcher]] became a Demon Lord.
** Creator/RikiyaKoyama is Azazel. Why Issei is [[CrazyAwesome crazily awesome?]] He's got [[Manga/MahouSenseiNegima Jack Rakan]] and [[LightNovel/FateZero Kiritsugu]] as his mentor.
** [[Creator/MaayaUchida Maaya Uchida]] is Irina Shidou. This makes her a [[RunningGag Self Proclaimed Angel]] with an [[LightNovel/LoveChunibyoAndOtherDelusions 8th grader syndrome.]]
** [[Creator/RyotaOhsaka Ryota Ohsaka]] is Vali. Guess [[LightNovel/TheDevilIsAPartTimer Sadao]] had a dragon in him all the time.
** Creator/HirokiYasumoto is Kokabiel. See RelationshipVoiceActor below.
** Creator/ShowHayami is the Patriach of the Gremory family.
** Creator/YuuichiNakamura is Sairaorg. [[Manga/FairyTail Gray Fullbuster, a Demon Slayer]], [[{{Irony}} has become a Devil.]]
* RelationshipVoiceActor:
** Although it was a short-lived one, Creator/ShizukaIto and Creator/HitomiNabatame reunite here as Akeno and Raynare.
** Creator/ScottFreeman and Creator/JamieMarchi played another OfficialCouple in ''LightNovel/BakaAndTestSummonTheBeasts'' (Yuuji and Shouko).
** The 2nd season of the anime reunites [[AyaneSakura Akane Isshiki]], [[Creator/MaayaUchida Rei Kuroki]] and [[HarukaYamazaki Mizuha Amagi]] from [[Anime/VividredOperation Vividred Operation]] but ironically their characters will never get to interact with each other in the anime.
** Also in the 2nd season of the anime, [[Creator/YokoHikasa Emilia]] [[LightNovel/TheDevilIsAPartTimer and]] [[Creator/RyotaOhsaka Sadao]] are reunited but at least this time, Emilia isn't out for Sadao's blood. But if Issei is hurt...
*** [[AzumiAsakura Emerlda]] was already there. [[Creator/HirokiYasumoto Albert]] pops up to but he's evil now.
*** Remember that [[BadassBystander awesome convenience store worker]] that threw paint balls at Emilia's attacker? He's [[YuuichiIguchi Saji]] over here.
** [[Creator/HirokiYasumoto Kokabiel]]: [[YuukiKaji Issei]], [[LukeIAmYourFather I am your father.]] [[Anime/AquarionEvol 12,000 years ago...]] And he's also [[VideoGame/AsurasWrath Asura]]. Though he got demoted from demi-god to fallen angel, no ''wonder'' the Gremory team couldn't even scratch him.
** [[Creator/YuukiKaji Issei]] and [[Creator/YuuichiNakamura Sairaorg]] have ''a lot'' in their list. [[Manga/DontenNiWarau Fortunately,]] [[VideoGame/FinalFantasyXIII they're]] [[Anime/GuiltyCrown allies]] [[Anime/AquarionEVOL this]] [[Anime/{{Durarara}} time]] [[Anime/FairyTail instead]] [[Anime/NobunagaTheFool of]] [[Anime/NobunagaConcerto enemies.]]
* PlayingAgainstType:
** In the dub, the cultured and flirty Devil Rias Gremory is voiced by the [[{{Lust}} slutty]] and [[SirSwearsALot foul mouthed]] FallenAngel [[PantyAndStockingWithGarterbelt Panty Anarchy]].
** Again with the dub, the perverted nice guy Issei Hyoudou is voiced by [[WebComic/AxisPowersHetalia United Kingdom]], the [[MeanBrit fake]] [[QuintessentialBritishGentleman British gentleman]]. At least, for the first two seasons.
*** For the third season, Issei gets ''two'' Playing Against Types: [[Creator/JoshGrelle he is voiced by]] the fearful UnluckyEverydude [[Manga/FutureDiary Yukiteru Amano]], as well as [[LightNovel/InfiniteStratos Ichika Orimura]], the one guy in an all-girls academy who has an UnwantedHarem [[CluelessChickMagnet and is all the oblivious about it.]]
* SleeperHit: Of the {{Winter 2012 Anime}} season. Heck, no one expected that the series would even sell 10,000 DVD [=/=] Blu-ray copies in the first week!
* WhatCouldHaveBeen: Supposedly, one of Issei's power-ups was to ''suck Rias' breasts''. Unfortunately, that was already too much for Fujimi Shobo, so the author resorted to something else.
* TheOtherDarrin: For the third season's dub, Creator/JoshGrelle replaces Scott Freeman as Issei, and Kelly Angel replaces Teri Rogers as Akeno.
** The dub acknowledges this in a very ''Series/{{Roseanne}}'' like way in the second episode.
--> '''Venelana''': You sound so different, Akeno!
* TheWikiRule: [[http://highschooldxd.wikia.com/wiki/Main_Page Sure thing, dawg!]] '''WARNING:''' Gets a little NSFW in some places.