k-on!
hirasawa yui
kotobuki hajime
1girl, ass, back, barefoot, bikini, breasts, butt crack, feet, from behind, greyscale, lineart, looking back, medium breasts, monochrome, open mouth, ponytail, round teeth, side-tie bikini bottom, side ponytail, sideboob, sitting, soles, solo, sweat, swimsuit, teeth, thong bikini, toes, undressing
photoshop (medium)