These are mostly my observations and interpretations of scenes that may suggest romantic implications between Yuu and Mika.
(I also enjoy writing analyses or random commentary outside of the ship, so when that happens, you'll find a * symbol in the...
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This scene appears after Guren tells Yuu about the "training" and Mika appears out of thin air to scold Yuu (nagging waifu Mika is amazing, by the way).
The panel with Guren taking in the look of the staircase leading downstairs could represent a negative foreshadowing. It seems that Yuu's "training" may lead to something even worse.
The staircase may also be a one-way sign to Guren, that to him, there's only one way in doing whatever he's planning. But this "one-way" may lead to a spiral down to disaster, of course.
The stairs look very simplistic, so this may represent that all three main characters are thinking just as simplistically about the situation, underestimating the danger ahead.
There's also the fact that this mansion is supposed to be very beautiful, so there's this generalization to Yuu that reviving his family will pave a "beautiful" future; however, he is forgetting the "small details" (represented by the small staircase in the large house).
No one really pays close attention to this "staircase" or the "small detail" indicating danger, except Guren (who stares down the stairs before walking down) and Mika (who, by the way, has good instincts, is absolutely smart, and is under-appreciated).
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This panel might symbolize Mika possibly being farthest away from the danger since he is the last one out of the three in reaching the bottom of the stairs.
Since he is aware that whatever they are doing may indeed be dangerous, he is the most reluctant in participating.
Guren and Yuu are diving into the danger, while Mika is still walking along with Yuu; thus Mika is still not devoid of what may be an impending doom.
