#corridor whispers

In the cowbell episode, Nanami sees an item in the social context of “expensive jewellery”, and treats it accordingly as a status symbol - even to the extent that she ignores the opinions and whispers of the people around her.

In the egg episode, Nanami has no social context for finding an egg in her bed - so she obsessively attempts to predict the reactions of others, so she can work out how she is meant to feel about it.