sei (bigaa), agnes tachyon (umamusume), umamusume, absurdres, commentary request, highres, 1girl, ahoge, animal ears, black necktie, black shirt, brown hair, chemical structure, coat, collared shirt, ear ornament, earrings, hair between eyes, hand up, holding, holding pen, horse ears, horse girl, jewelry, long sleeves, necktie, open clothes, open coat, parted lips, pen, red eyes, shirt, short hair, short necktie, simple background, single earring, solo, sweater, white background, white coat, yellow sweater