Well, luckily she ain't a homewrecker. Or so it seems~
Vsauce theme plays
Koyuki's blackmail seem a bit weak. But why would she be targetting Haimiya specifically?
We saw in this panel that Koyuki has friends, so she could've just asked either one of them to hold their shifts.
So, why of all people, would she choose Haimiya?
There might be a chance that she wants to get to know her in a way, but decided to do so in a roundabout way. By making Haimya do this part-time of Koyuki, basically introducing herself. Cuz when it comes to romcoms, saying that a character has a part-time job is like them revealing a big secret
So her getting Haimiya to cover for her shift was her way of saying "This is me. This is my life."
We'll be seeing what Haimiya will do here in the daycare. And we'll be seeing the things that Koyuki usually does here, like maybe the other people working on the daycare would talk about Koyuki, or the kids themselves would talk about her.
I love this way of introducing her, and we'll also see if she's a nice girl. But if she works in a daycare, Imma say that Koyuki is exceedingly nice and caring. Well, even her weak ass blackmail suggest she is nice.