Mettafell Rule 34 rule 34 ambiguous gender blush clothed clothing duo girly hair humanoid long hair machine male male only mammal mettafell mettaton mettaton neo monster open mouth penis robot sharp teeth simple background smile teeth tongue underfell undertale undertale fanfiction video games yaoi 1994781
rule 34 2016 balls blush duo english text fan character gay albino robot girly hair heart humanoid machine male mettafell mettaton mettaton neo multi arm multi eye multi limb multiple gentitals penis robot selfcest sex sharp teeth simple background smile square crossover teeth text underfell undertale undertale fanfiction video games white background yaoi 2045491