The series is only due to be two volumes long; I don't know what the original plan was, but the mangaka has marketed the second volume as being due to the success of the first chapters (which is almost impossible to measure given that it's a web manga). Perhaps we would never have had a present day arc, but I'm not sure how it would have ended originally.
I haven't read ahead (there are a few chapters more already published then there are only two chapters left, due to be published at the start of 2026) so I don't know what the rest of the series chooses to explore. Sumino's (presumably?) repressed sexuality? Further delving into Aoki's clear coding as autistic? I don't know if this is a series that is aiming for a happy ending, such as one can be possible here. Whatever the case, it's an impressive series for many reasons; it's brilliant to see a gay "romance" at the centre of a seinen manga, particularly one as artistically distinct as this.