yeah, that tracks.
She put a bunch of effort into his appearance to make him "suitable" for her, and of course others are going to notice and shoot their shot.
Question of course being: what Toiro is going to do about it, now that she's realized her feelings for him are growing deeper and deeper. They might as well be dating now even by "conventional" labeling, but they're still not romantically involved in any way (as shown by this chapter, of course). So someone coming along who seeks to take that step with him, where she herself isn't quite able to as of yet, could ostensibly pose a threat to this cover-up they're running.
Not that Masaichi is likely to care or bite, of course. Unless this is some other unintroduced-but-historically-significant person that will have a pre-established rapport with him, or something. I hope that's not the particular case here, but this is seemingly being set up as something of significance that represents the next arc of the narrative.
thanks for your continued work on this series.