3girls, 5pb_(neptunia), antenna_hair, asphyxiation, azur_lane, bdsm, black_hair, black_skirt, blue_hair, blue_headwear, bondage, bound, breasts, buttons, closed_eyes, cloth_gag, crossover, double-breasted, gag, gagged, grey_jacket, improvised_gag, jacket, kanojo_okarishimasu, kurotoi, long_hair, multiple_crossover, multiple_girls, mummy, neptune_(series), over_the_mouth_gag, pain, pink_eyes, prinz_eugen_(azur_lane), red_eyes, sarashina_ruka, school_uniform, short_hair, silk, skirt, spider_web, trembling, twintails, white_hair