Rule 34 Dev - 2d absurd_res alien ambiguous_gender arthroopd arthropod duo_focus feral gay greyscale group half-life half-life_(series) hi_res human male_only mammal mizzyam monochrome pencil_(artwork) penetration strider_(half-life) strider_(species) surprised synth_(half_life) traditional_media_(artwork) video_games voyeur what yaoi|2131974216