Another solid chapter.
I'd forgotten a few things, so I reread part of chapter 1 and paid more attention... Right, he was a 3rd year middle school in the track team, that's when he met Kisaki by chance, and then 6 months later when he started high school, Kisaki ended up in the same class as him.
Somehow, I'd skimmed the chapter far too much, and mentally remembered it as a sort of "a week later, Kisaki just suddenly transferred into his class" sort of development. So, the timeline with how she's known his mother for 6 months makes perfect sense. It also makes sense that with her surveillance/spy abilities, she could use those 6 months to find out what high school he planned to attend and apply to it too (probably snooped his mail at night, or planted bugs on his mother) and make sure she ended up in the same class as him (probably either snuck into someone's office and made subtle alternations, or did some social engineering with the person in charge... or maybe more creative/unethical influence methods).
Definitely curious about what her family life is like, too. Probably my ideal scenario would be that she's from a rich family that pays no attention to her... that, or her family looks like a perfect family to Haruka, but they're actually threatened by her into doing so, and are living in fear of her. (Anyone here read the web novel Ward? Never mind...)