Zero escape is a great game. You should play it. You know who's not great? This guy.
What's the work?
Nine persons, nine hours, nine doors is a puzzle/escape room visual novel with multiple endings. It involves nine strangers trapped in a ship that will sink in nine hours. There's also some stuff about mind reading and morphogenetic fields.
Who is the character/What has he done?
Gentarou Hongou was a CEO with prosphagnosia. Upset that he wasn't able to find a way to recognise faces, he came up with a plan to test morphogenetic fields.
He kidnapped 18 children (nine pairs of siblings) and forced them to play a death game where they would have to give information to their siblings using only their minds. When a brave police officer came onto the ship to rescue these kids, an enraged Hongou took Akane and locked her in an incinerator, smiling with glee as she was about to burn to death. Akane used what she had been through to project herself ten years in the future to rewrite her past.
Her and her brother set up a replica of the game involving vital people in this event (kidnappers, victims, and family members.) Hongou, going as Ace, was one of these people and the only one apart from the conspirators to realise what was going on. Desperate not to have his cover blown, he tricked one of his co-workers, co-conspirators into getting himself killed to stop him from revealing his company's intentions to the group.
To gain the trust of everyone else, he portrayed himself as a fatherly figure, acting kind and affable to everyone around him. This was merely an excuse to gain the trust of everyone as he worked to save himself, identifying and killing anyone who could blow his cover. He tried to kill Light Field, a man who knew who he was, but accidentaly killed another of his co-workers due to his prosphagnosia. Unfazed, he drugged himself to prevent the body from being found, waiting for the right opportunity to sneak off and murder another one of his co-conspirators. He bides his time waiting for the right opportunity to murder everyone else, actually succeeding in one ending, mercilessly killing everyone for their bracelets without a shred of remorse.
In another ending, he kills Clover, a teenage girl due to her being one of the children he kidnapped years ago. He taunts her blind brother (Light) about her death and proceeds to hold one of the mothers of the children he kidnapped hostage to get into another room. When his plan is prevented and he's backed into the incinerator he tried to burn Akane in, he pleads for his life, shooting Light many times when he refuses to let him go.
In every ending, he shows no remorse for his actions, actually enjoying the harm he inflicted on people. He has no qualms about hurting children of putting people through pyschological distress for insanely selfish reasons. He's a cruel, cold man without a shred of humanity with a clear sense of right and wrong and a complete apathy to the suffering he causes with his actions.
While the zero escape franchise does have some other nasty characters, none of them are as malicious and sadistic as Hongou, who deliberately targets children. He's also the first major villain, meaning that he has no competition. While Akane is an anti-villain grey zone, Hongou has no such preventions.
None. His prosphagnosia is a terrible reason for kidnapping and torturing children and while his co-conspirators are not good people, he murders them in cold blood to save his own skin. He's fantastic at hiding his true colors, but drops this facade in an instant when people are onto him.
I think he's an easy yes.