rule 34 2boys accidental circumstance accidental erection anal fingering ass background badly drawn black hair black shirt blonde hair blush bottomless color dave strider dialog doctor glasses gloves gynecological table homestuck horns karkat vantas labcoat legs held open male male only medical medical examination ms paint adventures necktie no visible genitalia on back open eyes prostate exam short hair speech bubble spread legs sunglasses text tinted eyewear troll uncensored underwear around one leg yaoi yellow sclera 883952