Puro

Personality Unlike the other more instinctual monsters Puro exhibits higher sapience than the rest of his species; he is a studious, curious, and compassionate being that humbles himself in wanting to become a better and better exemplar of his species. Though wary of humans, he is fascinated by them and even wishes to become friends with one. As a dark latex beast, he is also a natural enemy of light latex monsters.

Puro points out in the Aquatic Area he is unable to swim, as his body's cellular density is too great. Since he doesn't need to breathe underwater however, it's of little concern besides getting his tail wet.

A low relationship with Puro sees the Betrayal ending playing out. After reaching the end of the Aquatic Area, he'll give up hope of escaping the building alive, as without a host body, he doesn't have long to live before regeneration destroys his newfound sapience. He devastatedly reveals he always doubted Colin could survive with the world outside. Hoping to spare his friend and himself from dying ignoble and lonely deaths, he opts to "transfur" Colin personally, trapping him in a hallway with no escape. The latter has been running from barely sentient monsters, and should know how utterly screwed he is at this point. The worst possible outcome is Puro fully assimilating Colin into himself. The second worst has him instead turn the latter into a blue-eyed version of himself, referring to him as an extension of his being under his control. Only the power of friendship and playing on Normal mode can avert this.