Murder at Dawn was a horror game developed by the Studio of Action. The game was released on PC on June 14, 2016, and on August 14, 2020, cross-platform play and cross-platform friend support were launched. There were two camps in the game, the killer and the escapee. Each camp had different characters to choose from. Killers and escapees had unique abilities and skills. The game's DLC chapter would bring new content and experiences, such as new characters, skill types, and maps. In addition, the game also launched a joint event with the heavy metal band Iron Maiden, launching a legendary suit inspired by Eddie. For the specific mechanics and gameplay of the game, you can refer to the strategy and guide.
Toge Inumaki is important too. His special cursed speech ability makes him stand out. Also, the principal of the school, Masamichi Yaga, is likely to be important as he is in a position of authority and has an influence on Gojo and the other students. There could be other characters like the members of different clans that also play roles in the complex web of the story.
It's hard to say for sure. 'Daylight' could be true, or it could be a creation of the author's imagination. You might need to do some research or read reviews to find out.