@donm527
That boy was hostile when Miku appeared. Hurr-durr go away, leader of the enemy faction! While it's not impossible he was referring to Miku, I see no convincing sign or argument based on how he reacted to her. Especially since she already ate their takoyaki, so nothing would really change if the guy give her one again later, which he made, and not Maeda. Miku already said it was delicious. It could be someone else entirely. Someone from the girls' side, or even another quintuplet for the lulz.
https://mangadex.org/chapter/682543/4
He is there with 5 other girls to select from, outside of Miku.
https://mangadex.org/chapter/682543/17
Maybe he is referring to the prominent, stand out-ish one that supposedly aims for Takeda.
Negi could give the middle finger to the Miku fanbase, but only at the climax of the arc, aka around 8 chapters later, if she is not the chosen one. But until that happens, he is not gonna pass up keeping up her chances with Fuutarou, therefore I really, really doubt that next chapter takoyaki boys gets the spotlight with Miku, and not Fuutarou as everyone would expect.
Also, Miku was looking for Fuutarou on Day 2 to walk the festival with him, while having a lovestruck face. She might have already kissed him before this.
https://mangadex.org/chapter/701842/27