I was wrong about the Kotetsu and Barnaby mini drama in the Super Prelude event.
This scene happens after Maverick is defeated, both are working in their office.
Kotetsu is in some kind of internal monologue about heroes, salary men and Maverick that ends up in him whining loudly, Barnaby, who was working until then, shuts him up. They talk a bit and the words “hero event” appears, then Barnaby tells Kotetsu “suki desu yo (or something that sounds like it)” twice and Kotetsu is confused, then Barnaby recites his rhyme, and Kotetsu is shocked.
Barnaby seems so proud of his masterpiece he even has the divine light when he finishes, Kotetsu goes back to his monologue but Barnaby interrupts him and asks him something Kotetsu answers with “opera, a capella” surely related to his rhyme and Barnaby gets mad.
I know crappy attempt but it was so amusing.