[FreshToku]

I wouldn't care if they have the actors for Tachibana and Hajime come on screen just to tell us directly that Garren is the 'secondary' of that show. It's Chalice in my eyes.

And while I'm here, Para-DX is the the closest thing to being Ex-Aid's secondary while Brave and Snipe share the spot of next most important side-character (which I think would fit the definition of 'tertiary' here). And that Punch Hopper is more prominent than Sasword by the end of Kabuto.

Though more often than not, I firmly feel like it really is just opinion anyway. 'Secondary' and 'Tertiary' change in definition from show to show and person to person on whether it means 'second and third most important riders', 'rider closest to the main character', or 'literally the second and third ones to appear'. It's all made up anyway. Like, within the context of a show like Agito, both G3 and Gills are meant to equally stand up as deuteragonists in the show, but in Ryuki, obviously Knight is the sole number two to Ryuki's number 1.