|KNF, aka Ketsueki|
Official art of Ketsueki with several effects equipped at once. (Source)
Ketsueki (血液) lit. Blood Liquid
KNF, called Ketsueki (ケツエキ/血液) in the dream world, is the main character of the fangame Nightmare Diary.
Ketsueki is a teenage male who, in the real world, has bloodstains dotting his face, hair, scarf, pants, and shoes. Once in the dreamworld, however, the bloodstains have vanished.
KNF is regretful of what he's done in the past, though if wanted he could easily kill with little afterthought of his actions, despite that that's what he's so regretful of.
In the dream world, however, Ketsueki is much more calm. He's precise with his words, making sure his meaning isn't misinterpreted by anyone on accident. He's shown to be kind and willing to listen to issues.
The personality differences between the real world and the dream world are a result of KNF wanting to live as his ideal self in the dream world.