I mean, their tongue is also purple

Their bloods are actually unknown. In the oldest ratyu batting day ( https://s.castle.xyz/45fvH29RQvXy ), dummies bleed black blood, how ever, in fist fighter 2 ( https://s.castle.xyz/X-t2IcTuNBdf ) they bleed red blood

i think so

O I never realized that

i think they are just so angry, that they are forming blood clots on their face