I'm not sure what the author's plans are, but things can go just two ways at this point:
- the author makes them actually split, attempting some half-assed story about the MC's adventures
- this chapter is just a cliffhanger and in the next few chapters something "big" happens for them to stick together
I could understand if this was some drama/psychological kind of story, but both the "comedy" and "romance" tags are there, which makes me doubt this development will go anywhere at this point.
I'm betting on the fact the "mysterious gaze" will come out next chapter, they will fight it/understand what's going on and for some reason they'll just stick together again.
PS: I also want a "harem" tag to not leave out the other girl, but a man can only dream at this point