Right, you just choose to forget she fucking pull a long face after Aya got a job interview invited by Kumagaya in chapter 7.
Do you think Koto wouldn't "suggest" Aya to quit the job?
Well, she definitely suggested that she shouldn't try to get that job (and acted like she was jealous of Kumagaya and Aya's newfound closeness). I'd say it's a safe bet to say that she will try, in the future, to make her quit... especially when she finds that there's a super dishy tsundere boy working with her, and he has an interest in her!
We keep discovering new things about the mcs every chapter. I'd never had suspected that Erika's place was a messy pigsty. And I certainly wasn't expecting Aya to be a clean freak who just can't let a messy room alone and won't stop until she has made it spotless. Koto is the only one with no surprises, she's a one-track-minded person whose whole life revolves (and has done so for the past 7 years) around Aya. And I'm kinda starting to agree with those who think it's, like, a li'l bit cringe.