Phenomenal pacing and atmosphere. I liked how the other characters would come in, not only did it help to progress the story but you can understand Kaori's feelings a bit more through these interactions.
Ultimately, I think the artists characterization of Asuka is pretty well done. I always got that sort of feeling from her. That feeling that she could be incredibly serious, but also very aloof as well. I understand totally why Kaori is so unsure of what she is doing with her. The description of kissing/being with her being like poison is incredibly apt. A woman's poison lips/eyes/etcetc is a very common line in literature and music, and has been for decades upon decades. That feeling when you can't quite reach another person, don't know what their motives are, but they are so attractive and seductive you go with them anyways. Very interesting. Ending definitely had a bittersweet feeling to it, but quite a few of these types of non-h yuri stories do. But in this case, it was impeccably well done.