Dusk Maiden of Amnesia/Fridge

Fridge Brilliance

 * Why doesn't Yuuko care about shamelessly revealing her astral body, but is deeply embarrassed by her corpse? Two reasons: O
 * One, Niiya is likely the first person to appear in years (or even at all) who can see Yuuko as she actually appeared in life. She's probably used to not caring how her astral body would look to someone who could see it, because there wasn't anyone who actually could see it.
 * Two: it's not her actual body, but just her appearance. She doesn't age, and we've had no reason to believe that she can get hurt. It's not a physical body and doesn't require the maintenance of a real body, so she doesn't treat it as "sacred" or "private." But her physical body is and was that, so she feels that it should be treated with such respect.