I know this may sound like a stretch but I just watched the episode again (in FULL color, nice and perfect) and could it be that...... Sheryl and Ranka are sisters?
But it DIDN'T help, that's what is confusing. I'll wait for the episodes to clarify before I speculate on anything. You all can say it has a NUNS logo but I'll wait to hear it from the show itself.
ZOMG you guys, Ranka does not have a "bump" under her dress, she obviously grabbed the front causing it to fold. I noticed it the first time I watched it. Stop getting all riled up about it.