Dr. Rivulet is a human general practitioner for artificial intelligences— People will book appointments for their AIs, and Dr. Rivulet will meet with the AI, and either help them through what's bothering them or simply fix them. He's a man with a friendly, open demeanor, and can be overly casual sometimes, but knows how to be serious and comforting when the need is there. He's incredibly knowledgeable, and struggles sometimes with connecting with actual humans.