Imma break their bone and stab those A-hole
This type of people are Trash and need to be Incinerate!

From the perspective of someone who enjoys the sciences. I'm quite irritated at the attempts to give Seiha an extreme scientific perspective, because the perspective she has is fundamentally flawed from a scientific point of view. Egoism is the word defined by the idea Seiha proposes in the previous chapter, that "one's self is the motivation and the goal of one's own actions." The thing is, Egoism isn't a scientific theory it's a philosophical theory. Egoism is hardly falsifiable, from a scientific perspective it can't really be proven or disproven, it's more of a set of beliefs than a scientific fact; and in philosophy logical argumentation is used to debate theories, many very sound arguments have been made against egoism, it isn't a unanimously accepted philosophy by any means.

So to apply "'true devotion' and the like are meaningless according to science" using the theory of egoism, as Seiha did, is extremely fallacious and incorrect. Rather "'true devotion' and the like are meaningless," one of the common tenets of egoists, is merely philosophically debatable, it is also hardly falsifiable, thus hardly scientific. The correct response to Seiha shouldn't be "sometimes science is wrong," but a correction: "that isn't so much a scientific standpoint as it is a philosophical one, and science does little in that debate," although I agree that sometimes science is wrong.

The attempts to make Seiha extremely scientifically grounded are making her look unversed in science, and it's painful to read. This isn't the first time it happened either, it keeps occurring in this manga, she keeps taking philosophically debated concepts and accepting them as scientifically backed truths.

What the hell's the explanation for her excessive rationalizing of emotions to the point she pretends she isn't afraid?