Even before Book 6 there were hints that Idia is living with the guilt of what he did to original Ortho as a child, asking in a vignette what he was trying to accomplish by equipping Ortho with so many different functions. “Installing the latest medical tools in you now can’t change the past…”
But Ortho insists that he likes how handy his body is. “I can do lots of stuff regular people can’t!”
Ortho can be protective of Idia: our first introduction to Ortho in the main story is instigated by Ortho crossing a room to scold Cater and Grim for gossiping about Idia, saying, “He’s not desperately lonely or anything, okay?”
He accepts Cater’s apology with, “I just don’t want anyone getting the wrong idea about Idia.”
When Ace wonders aloud if Idia does not have any friends who would be willing to help him out during Phantom Bride Ortho responds, “Can we PLEASE focus on the mission and stop dissecting my brother’s lifestyle?”
After explaining to Kalim that Idia canceled plans to play outside after ranking lower than expected in a video game Kalim responds, “Spending quality time with your sibling is way more important than some game.”
Ortho immediately defends Idia, saying, “Don’t diss my big bro! Idia’s nice and smart and the best brother ever. He’s just…kind of an oddball.”
Ortho is concerned about looking for the missing students during Spectral Soiree alone, but says, “I’ll do whatever it takes to get Idia back!”
When Idia goes missing during Vargas Camp, Ortho abandons his responsibilities to search for him.
Idia refusing to spend time with Ortho (despite previous plans or promises) is not unusual.
Ortho has a voice line about inviting Idia outside to play Spelldrive for some exercise, “but he said no…again.” We also see Ortho invite Idia to spend time together on a Saturday where Idia refuses in favor of plans with Muscle Red, and Idia being very tempted to refuse to join in the Spectral Soiree Halloween party, but “…considering everything you did for me today, it’s hard to say no…”
Despite his role in trying to get Idia to interact with others (re: tricking him into going to Epel’s hometown alone and leaving him to his own devices during Vargas Camp 2) Ortho seems to have issues with forcing Idia to do things against his will, and he is very much aware of it.
Despite his eagerness for Wish Upon a Star Ortho says he doesn’t want to force Idia to perform if he really doesn’t want to despite his desperation to create new memories.
Ortho says, “If another ceremony comes up, could you drag my brother here, even if he’s kicking and screaming? I’d probably cave in and relent…”
Ortho also makes sure Idia fulfills his punishment during Vargas Camp 2.
Twisted Wonderland Reference Note 