Koi is a shy grem who spends most of his time studying wildlife as a marine biologist. When he's not working, he's either carving sculptures from driftwood or playing with his reef crawlers he keeps as companions.

He generally keeps to himself and prefers to only be around those he holds close. He is autistic and nonverbal and struggles with communication, often relying on his boyfriend to help him communicate with others since Koi struggles to properly convey his thoughts.