I think Kei, who knows his older brother the best out of anyone, realizes that Masayuki is being poisoned by Takano.
Wait FRL?
Isn't it just too weird how Masayuki keeps collapsing with stomach aches whenever Takano gets near him? Especially after eating or drinking things. And that whole business with the prima donna and her food was clearly sabotage. I think Takano wants that company more than he's letting on. The whole smiley-faced business is starting to look a little fake.
I see I see. You've got a point there. I can't wait to see what happens next.
Of course, it might just be irritable bowel syndrome aggravated by stress ... pfft.
I'm pretty sure he's being "poisoned" - even if it's only mentally. Be it out of spite or unawareness, he's being kept in a poisonous loop which can only result in him collapsing or bolting for it (the latter would be preferable and the healthier solution).
Him being able to stand up for himself and setting boundaries for others to notice would be far off as he's been kept on that leash for so long. He's like an elephant trained by heavy chains and kept with a flimsy rope at the end. He'd need rest and a safe harbour to aquire the mindset needed to break free on his own volition.
But well, that's just my own take on this fictional character, and the goal the author has in mind surely differs from the one I'd project ^^
That's a very subtle story line for most yaoi, and I really like that. From the heft and swing of emotional saturation so far (to use a confusing analogy), I doubt this mangaka goes for the overly subtle approach. But, hey! One never knows. If it happens, I, for one, will be giggling like a little girl.
Is the older brother poisoning him?