Tragic ending =/= mature. If we follow that thinking a tragic end eould be just as formulaic as a HEA. I think as long as the ending is realistic to the story it'll be satisfying. I can see this ending tragically very easily cause they're yakuza, but I also see them working something out (esp cause yashiro isn't a full fledged yakuza anymore)
Nah, if this story ends tragically not only would I end myself but I would also think the author chose the easy way out. I feel like a tragic ending is honestly very predictable and easy to achieve while a happy ending would be challenging to execute therefore making the story more interesting. I think it would be really cool to see how the author works towards a happy yet realistic ending rather than just making them both died at the end or something
At this point, after all this build-up, a cookie-cutter happy ending just won’t do. I’d find a tragic conclusion far more satisfying, it’s the only way this manga could stand out as a classic. There are already plenty of stories with shallow “happily ever afters.” This one is meant for a mature audience and it deserves an ending that reflects that