It's a good job the Japanese aren't racist, otherwise this could be severely misunderstood.
No doubt a traditional Japanese demon: as with buddhism; or monkey warrior.
Racism as a whole is dead except for the people who constantly point it out, which ironically reinstates any perceived rift between races. I don't see how this image could possibly imply racism even if it wasn't Japanese. Just because a gorilla is black they represent black people? Is Akitsu Maru expressing her black pride then? Let say the gorilla was intentially meant to represent blacks. How would this be discriminatory in any way? The gorilla is offering the girl a flower, probably a near universal symbol of friendship/love.