![1girl arm_ribbon arm_up armpits bad_id bad_pixiv_id bare_shoulders barefoot black_hair blue_eyes blue_ribbon bow breasts cleavage cleavage_cutout covered_navel dress dungeon_ni_deai_wo_motomeru_no_wa_machigatteiru_darou_ka feet_out_of_frame gloves hair_ornament hair_ribbon hestia_(danmachi) leg_up long_hair looking_at_viewer medium_breasts open_mouth pencil_dress rei_no_himo ribbon short_dress simple_background sky sleeveless sleeveless_dress smile solo standing standing_on_one_leg star_(sky) starry_sky sumeragi_seisuke twintails very_long_hair white_dress white_gloves rating:s score:11 post #1976702](/cdn_image/preview/e2/c7/e2c7717210012fa217d6f874420b67a3.jpg)
A pencil dress is a slim-fitting dress with a straight, narrow cut. Generally the hemline ranges from skirt length to miniskirt length, and is tailored for a close fit.
Hestia's white dress is an example of this, due to the skirt portion of her dress fitting tightly around/below her hips.