FURVERT!

1:1 alien alien_genitalia alien_planet alternate_universe announcement announcer anus asmallotter big_butt big_penis biped bipedal_feral black_mesa blush blush_lines brown_body bullsquid butt butt_slap claws detailed_background electricity english_text feral first_aid_kit floating_object floating_rocks genitals glowing glowing_eyes glowing_plants growling half-life hi_res levitating_object levitation lightning looking_at_viewer looking_back looking_back_at_viewer male medical medical_instrument monster motion_lines penis plant portal presenting presenting_anus presenting_hindquarters presenting_penis raised_tail rear_view rock scientific_instrument slap slapping_own_butt slapping_self slightly_chubby solo sound_effects space spires tail tail_anus tentacles teratophilia text valve valve_corporation xen_(half-life)xen_creature yellow_eyes