Chapter 7 page 12

Sibao and Emmie chat about things that are cool. Emmie gets excited and waves the laundry they are holding in the air, then turns and runs to Morio for inspiration.
Sibao: And the Prince is extra super cool ‘cause he’s undefeated!!
Emmie: Oh yeah? Why does he say “protein of the future”? What does that mean?
Sibao: It doesn’t mean anything. It’s just supposed to sound cool. That’s how catchphrases work.
EAT THIS!! PROTEIN OF THE FUTURE!!
Emmie: Huh… I want a catchphrase too! Morio help me think of a catchphrase~
Morio: OK.