Viper as seen in Episode 4
|First Appearance||Episode 4|
Viper returns in Episode 18 with an apparent interest in reconnecting with Dororo, as well as Keroro, who was revealed shortly before to be Dororo's missing little brother. Episode 19 further drives home his promiscuity and his ever-widening/spiraling family tree.
Grandma Viper: "Viper!"
Keroro: "'Son?!' What the hell is wrong with your family?!"
Viper: "It's a big family reunion! Bastard sons... Mom-son... Dad-train..."
Keroro: "You know what? I don't want to be in your family anymore!" - Episode 19
- Ezekieru, editor for Geass TAS, was originally asked to voice Viper, but it didn't work out and he suggested his friend BigTUnit1 instead. BigTUnit1 became part of the lead trio behind TheMidnightFrogs, a writer for the series, recurring voice actor, and a regular on TheMidnightFrogs Podcast.
Viper's father appears in the Episode 7 flashback. He was a kindly old man who helped the young Zeroro, Keroro and Giroro find Viper's hidden treasure. He however seemed to have memory problems: not only couldn't he remember his own grandson, he had been on that same train since before his mustache turned from brown to gray.
He returned in SFA19 for a voice-only cameo, having apparently been on the train so long that he fused with it. He returned in SFA24, this time fused to Shurara's refrigerator by Robobo, revealing that it was because of Robobo that he was previously fused to the train. It is unknown if he ever escaped after Shurara was defeated. He was voiced by ThornBrain.
Viper's "mom-son" appeared in Episode 19 on the same train as Dororo's Mom for no explicable reason. She is Dororo's grandmother, but she is also apparently Viper's son. Her only purpose in the episode was to emphasize how screwed up Viper's family tree is. She was voiced by Travis in a slightly higher Viper voice.