Shower scene wasn't as bad as the last. It seems Stella had a sister as cute and positive as Azmaria by her side, smiling to keep her going, one who most likely fell due to her 'clumsiness' and since then has been missing. That would make sense why she was so harsh when Azmaria reminded her of her sister and it would make sense she was the one she's looking for.
* take your time *
