Toshio did propose to her, but it wasn't for a wedding. More like a "promise" than anything else, a bit like "promise to stay loyal to each other" until Toshio comes back. And maybe once they are adults and reunited, they would get married ~
I hope it answer your question (> w <)
Also, thank you for looking forward to the other projects ! I hope you will like them as well (a little something I did for a otome jam is almost ready, so I think it will be released in a few days) ♡