Genya Arikado

Genya Arikado is a member of a top-secret Japanese government agency. He tells Soma Cruz that he must reach the Throne Room when he finds that he is trapped in Dracula's Castle, which has been sealed by an eclipse. Arikado is a frequent visitor to the Hakuba Shrine and an associate of Yoko.

Castlevania: Aria of Sorrow
Arikado makes quite an appearance in Aria of Sorrow as he tries to provide helpful information to Soma Cruz while roaming around the castle.

When the game starts, you will immediately see Arikado and he will tell you to go to The Master's Chamber.

If your player manages to defeat Graham Jones in the chamber with the corresponding souls (Flame Demon, Giant Bat, Succubus) Arikado will tell you to defeat Chaos (Defeating Chaos will let you find the real ending).

Castlevania: Dawn of Sorrow
Genya Arikado makes yet another appearance in the sequel of Aria of Sorrow. This time he also returns as a playable character in Julius Mode (as Alucard).

Castle Entrance
''So you've decided to join us... Did you have a pleasant nap?''

''Skip the introductions. I have a few questions, and I need answers now.''

Why have you come here?

We're in Dracula's Castle.

No. We are inside the solar eclipse.

Well, it's like this... ''Huh?! An enemy!'' (defeats enemies, save for one Winged Skeleton) ''Damn! Protect the girl!''

(after Soma gets soul) So it has awakened.

The spirit of the creature you killed has just entered your body. You have the power to absorb the abilities of the monsters you kill.

''You have gained the power. Now you must go to the Master's chamber.''

Do you not wish to return with your friend to your own world?

''Go to the Master's chamber. Then, you will understand everything.''

''No need to worry about her. I'll put up a protective barrier.'' But death will most certainly find those who stay here too long.

''Yes. Only you can save her from a painful death.''

I, too, have things I must do within these castle walls. ''Go. Set forth! Both your own life and hers are at stake.''

If players tries to talk to him, he says "Go. Set forth! Both your own life and hers are at stake.", again.

Trivia

 * In Castlevania: Judgement, in Alucard's ending, it is revealed that Alucard (under the alias of Genya Arikado) infiltrated a secret Japanese government agency shortly after the Demon Castle Wars to prepare for the Castle's return in 2035. While part of the agency he apparently keeps an eye on the Hakuba Shrine (during which he encounters the caretaker's daughter Mina) and works with Yoko and the Church. It is likely that both he and Yoko also kept an eye on the activities of Graham Jones and his followers.
 * In the opening of Castlevania: Aria of Sorrow, Arikado can be seen destroying multiple enemies with a magical attack. This is presumably Alucard's Soul Steal spell.
 * While under this persona, Arikado's hair is black. This is most likely the work of his (Alucard's) magic power, as when playing "Julius Mode" in Castlevania: Dawn of Sorrow, which takes place soon after Soma embraces the role of Dark Lord, Alucard is encountered with his usual white hair.
 * Arikado's name is based slightly off of the Japanese romanization of Alucard, which would appear phonetically as "A-ru-ka-do".