Thanks for the chapter.
As an aromantic person myself, i feel a bit conflicted about luna. Its somewhat understandable to be wanting to try out dating despite never haveing had romantic feelings and at the time she started dating mai she also wasnt even aware of her aromantic status. However, leaving that part unexplained for so long is absolutely something she shouldnt have done. While you never owe someone an explanation for breaking up, i think that if you want to stay friends with someone after you stop dating them, its important to communicate why you broke up with them in the first place.
Here, she cause undue pain and sadness by making an unfinished explanation and she only resolved it after said person finally got the strength to move on from an external source(and even there she tried to interfere depite it being absolutely none of her business).
that said, i am glad that she was able to explain herself and even apologize and remain friends, as i am a sucker for communication and happy endings