Two high school friends become sex friends, semi-permanent roommates, and then, maybe, lovers. Mostly an investigation into the boundaries we draw between ourselves and others in our life, and how much we need to negotiate those boundaries when we strive for intimacy or a deeper relationship. Realistic, slow, and not much happens except for the central conflict (which is resolved, primarily, off-screen), but sweeter because of that, because you're truly cheerleading for their success.
NightS is my favorite of Yoneda Kou's works, as it perfectly encapsulates her ability to mesh plot with sexual/romantic tension. The relationship is consummated, but only superficially. Reduced to the tropes it sounds silly and predictable, but Masaki is sexy/older/wary/flirtatious-but-dangerous honed to knife-sharp accuracy, and the dialogue between him and Karashi is endlessly entertaining. As always, Yoneda Kou works magic with lightplay/shadows in her art.
Yakuza meets ordinary dude (who happens to play piano), yakuza has sex with ordinary dude, ordinary dude develops feelings, things do not go well, in a variety of ways. Tragic, angsty, and wonderfully sincere, this is primarily about the pain of wishing for someone to be happy, and how to be happy against all odds. Ambiguous ending depending on your interpretation. Worth a reread, every time.
Sayonara, Heron