The café / villa owner seems to be the new fiancé if he had to take that out of place phonecall. Assuming we've actually seen his real self (kind) and how he must've figured out Mei and Yuzu's relationship one way or another, isn't this actually a nice turning point? Since there's a high chance he'll find a way that those two can be together.
He seems like the type that doesn't give a dip about family traditions, working on his own like that instead of working in a company that his family owns (if that café is not their family's that is).
Yup my thoughts exactly. And he has been hinting to Yuzu that "He'll be brave too" since Yuzu had inspired him so. I don't think Mei is actually engaged now. I do think that there is a suitor/fiance in the pipeline and that person is this guy. I can't see why she'd still be engaged to an opportunistic teacher with a shitty reputation. I mean she IS the gorgeous and prestigious Mei Aihara, a catch if ever there was one.
I do believe Mei in her own way is trying to fight tradition. Wanting Yuzu to kiss her in public. Wearing the ring. Bit marking her. I daresay Mei seems to want this relationship to be out in the open more than Yuzu does.
Also as an awesome twist... Mei's mother would reappear and this time with the reason why they divorced.... I'm assuming she also is from a prominent family and as per tradition was promised to Mei's dad.... But she divorced him and moved in with her highschool lover... her girl lover!! Maybe it's just me but I'm liking the drama! I just wish there were more memories that were made in their lame summer trip!
