Actor Allusion: In the English dub Gai is voiced by Brett Weaver, who also played Roy Focker and was scheduled to play Kamina before ADV lost the license.
Acting for Two: In the Mexican Spanish dub of the TV series, Desirée Sandoval voices Megumi Reynard and Ryoko Subaru, Diana Nolan voices Ai, Eri Uemura and Harumi Tanaka, Araceli Ramírez voices Sayuri and Junko, and Mario Hernández voices Jin Fukube and Haruki Kusabe.
Marth Debuted in "Smash Bros.": A very egregious case happens in the Mexican Spanish dub of both Prince of Darkness and the TV series: The movie came first in Spanish and the TV series many years later due to Locomotion (the network who licensed the movie in Spanish in Latin America) only managed to get the rights of Prince of Darkness, due to the Japanese licensors asking very unrealistic petitions for the rights of the TV series in Latin America. The TV series was licensed in Latin America by Animax (previously Locomotion), albeit with a different voice cast from Cuernavaca.
The Other Darrin: As previously mentioned before, the Mexican Spanish dub of TV series has a different voice cast, partly due to the time gap between the licensing of both Prince of Darkness and the TV series (the movie was released in Latin America in 2001 and the TV series about 2005) and partly because Animax decided to use another, cheaper voice acting studio in Cuernavaca (Intertrack in this case, since it moved from Mexico City in 2002), when the dub of the movie was dubbed at Román Sound, also based in Mexico City.
Real-Life Relative: Akito and Ruri's Japanese voice actors are husband and wife. Thankfully not replicated in-series, albeit doesn't prevent Ruri's dialogues towards Akito and vice versa from sounding more passionate than those between Akito and Yurika, the official couple of the series.
Subverted between the Mexican voice actors of both characters in Prince of Darkness: Despise having the same last name, Ariadna Rivas (Ruri) and Emmanuel Rivas (Akito) aren't related.
Technology Marches On: While the series did accurately predict that VHS tapes would be obsolete in the future, it does not do the same with floppy disks.