is not that the dude doesnt notice akari's feelings, is just that this whole married situation is fucking up everyone perception of things, he's like nope she's just doing it for the course, and the childhood friend acting was too good when they started the whole thing, and even after that she's not doing anything to properly advance their relationship, its a big ass clusterfuck of a situation on top of the regular ''childhood friend wont advance the relationship till a rival appears'' trope