My first reading and reaction was 'Wtf? What's that shit?' I was disappointed but now, I think the end corresponds to the manga. I didn't expect anything different.
To be quite honest, i had a slight bit of hope, mostly due to the short haired girl acknowledging the other one's feelings. Sometimes that leads to a "Hey, maybe i like that person too?" moment in romance stories. Seems that it was just me putting blind faith into something that didn't deserve it.
It's not even a bad ending, its one of those endings that leaves you like "Huh? Thats it?" like the ending to Nanashi no Asterism which had potential, but early cancellation killed it. Maybe this manga needed early cancellation as well.