->Live Actress: Runa Natsui
Ryusei's old classmate from Subaruboshi High.
* [[spoiler:BewareTheNiceOnes: Uses a pipe to hit the Dustards something nasty. [[ActorAllusion This might not]] [[Series/SamuraiSentaiShinkenger surprise some]].]]
* OnlyFriend: With Jiro out of the picture, she's the only one able to fill this role - but it takes time.
* ShrinkingViolet: [[spoiler:Although this may be just be a result of the Aries Horoscopes' rule.]]
* WeAreNotAnItem: [[ShipTease She's working on that, though.]]
** [[spoiler:ShipSinking: Only for Ryusei to tell Tomoko at the finale to come visit him and to tell her that he's not dating Mei.]]
->Live Actor: Ryusei Yokohama
Ryusei's best friend who fell into a coma following a failed attempt to activate a Zodiarts Switch.
* ConvenientComa: His current state. [[spoiler:He returns for good at the end of Episode 32.]]
* IJustWantToBeBadass: He just wants to be as strong as his best friend. [[BeCarefulWhatYouWishFor Then he received a Zodiarts Switch...]]
* MeaningfulName: "Iseki" sounds like ''inseki'', another word for a meteor (besides "Ryusei", which ironically is the actor's real name.)
* OnlyFriend: The only one Ryusei would consider [[spoiler:initially]].
* TooGoodForThisSinfulEarth: Played with. [[spoiler:Jiro survives but, when cured from the effects of the Switch, he is shown to be so pure that he loses the will to live on hearing what Ryusei did to save him. He gets better though.]]
* [[spoiler:WhatTheHellHero: Calls Ryusei out on his treachery to Gentaro all to revive him, before relapsing due to losing his will to live.]]