Honestly, probs to the author for giving us a ending for each girl. It satisfies our personal ships gives our best girls the ending they deserves. Sensei was my best girl but I no hope of her winning. The fact that she even got an ending is blissful to me.
In my headcanon this is the harem route where Nariyuki ends up with all the girls. What exactly constitutes "all the girls" (aside from the 5 heroines) can be open to debate.
In the end I liked this series and I'm glad the author chose to give each heroine her happy ending.