Rule 34 Dev - 2boys bite_mark blush class_3-z ear_fins gay gintama gintoki_sakata hair_over_one_eye male male_only merfolk merman monochrome necktie nipple_piercing nipples off_shoulder official_alternate_costume open_shirt pecs smile takasugi_shinsuke teacher tears wy3163561826160 yaoi youkai|13827574328