Need a place to start? ttps://github.com/iccanobif/gikopoi2/tree/master/static/characters is the gikopoi2 character folder -- character/front-standing.png can grab a file, such as ttps://github.com/iccanobif/gikopoi2/blob/master/static/characters/new-captures/hentai_giko/front-standing.png

On my computer, a character file is roughly 70x45 px (probably different on your end).