Come on, MC, she is just using an useful ability on someone who is more than willing to have it used on her and wouldn't be affected in any negative way (unless the power-up has some sort of drawback I missed or wasn't mentioned yet), which seems like the logical thing to do when your clan is on risk.
You can't compare someone doing such a harmless thing to your asshole grandfather who would make people forcefully bow to him because "muh authority".
@Acolytus "But, but... muh dramas!" (^_~) More seriously, your point is completely valid... but what's a manga without some pointless angst, generally in the form of "My loved ones would hate me if they knew about X"?
Also, I suspect the drawback will be something like an adrenaline surge that lets you surpass your normal limits - you might be able to lift a car off your child in an emergency, but you also might hurt yourself and not realize it until later.
@Filuth@monstergelo I believe it's some of both, leaning more toward "a form of erotism". Black tights (which always look like they were spray-painted on, even IRL) are definitely more subtle than pantsu that look like they were spray-painted on, but they're in the same category.
@Acolytus UBW. Shiro Vs Shiro. Absolute ideological battle, both are equally idioealistic, yet still killing each other to make their futile ideals true.
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Oh, the power to make character design more fancy and thus make his plot armor thicker as character is more relevant.