I'm already pre shooting a chapter where the two of them will lose sight of each other. One continuing her prostitute's career and the other marrying a man and having some babies.
Time skips, until they are grannies and randomly encounter each other. They will share their experiences after they break off and finally confess their feelings and regrets not being with their self when they were young and promise to be with each other until their last day.
And of course, the BFF will never confess her feeling for the MC and even though she did, she will get a big Nope from her. And she will go marry a man and have some babies.
The end.
Yuri story setup in a historical old Japan (more or less accurate) are most of the time frustrating and full of wishful wishes. When it doesn't end with the main couples acknowledging their true or possibly starting dating, we get the "I'm already married, and I have kids, so I can't date you even if you are the love of my life" or "I'm going to travel all around or study in another country so adios my love" or the unpopular one "dead lesbian".
I would really like a story where the couple decide to live their life even though everyone is against them and without hiding their self behind a (fake) marriage with a dude.