Apart of me mourns the fact Saiko isn't canon to the manga because it would have been very interesting if she was a long-term rival to Momo.
And also really, really funny.
I mean. She's basically Yaomomo's own personal Monoma.
Saiko was proud and ego driven, and had total faith in her own intelligence. Her Quirk is literally IQ (Putting aside the fact IQ is kinda crack science but y'know.) Her power is being smarter than everyone all the time.
And yet she was outsmarted by Momo.
Momo, without the need of a intelligence based Quirk. Outsmarted a natural born genius whose thoughts and planning was getting quicker every time she drank fucking tea. And you're telling me Saiko was OKAY with never getting back at her? Oh no girl got both crush and a new nemesis that day.
I 100% believe not only does Saiko's school never stop hearing about a "Yaoyorozu" but is forced to witress Saiko's caffeine fuelled obsession with getting her own back in the form of more and more pretentious mind games. To which Momo is like "Oh she wishes to play chess with me? That's lovely I am glad she holds no ill will against me for the exam :)"
Momo wins the game and Saiko breaks her cup with a shaky smile and watering eyes.