Rule 34 Dev - 2010s 2019 2boys 2d 2d_(artwork) animated_skeleton artist_name artist_signature blue_blush blush bottom_sans crying digital_media_(artwork) duo elemental_creature elemental_humanoid fellatio fire_elemental grabbing_head grillby grillsans hand_on_another's_head hand_on_head head_grab humanoid male male/male male_focus male_only monster monster_boy orange_body partial_male penis penis_in_mouth sans sans_(undertale) seme_grillby sex skeleton skerbbie solo_focus tears top_grillby trembling twitter uke_sans undead undertale undertale_(series) unseen_male_face video_game_character video_games white_background yaoi|1030094