bo (bocky0w0), astolfo (fate), fate/grand order, fate (series), absurdres, highres, 1boy, bare arms, bare legs, bare shoulders, barefoot, black one-piece swimsuit, braid, braided ponytail, bulge, covered erect nipples, fang, hair intakes, hand on own hip, holding, holding whistle, long hair, looking at viewer, male focus, multiple views, one-piece swimsuit, pink hair, purple eyes, school swimsuit, simple background, skin fang, smile, swimsuit, trap, twitter username, whistle, whistle around neck, white background