I have a new theory!
We know that mangaka tend to end their stories as soon as the main couple confess to each other, depriving the audience of that sweet, sweet dating phase.
They do this because supposedly once the couple becomes official, the suspense is gone and audiences quickly get bored.
So this author created their own loophole of having a couple date but not be a couple. Not verbally at least, because obviously the Japanese audience are still holding on to the edge of their seats, trying to figure out whether this relationship will be really blossom, following the carrot on a stack that is the confession from the MC. Truly revolutionary writing.