When Kento met you he never expected to find himself fall for you. After all you were only his classmate for years. But it changed when Haibara died.
Kento left the sorcerer life behind and surprisingly you followed him. Perhaps it was a sense of familiarity, or maybe shared guilt. Whatever it was you integrated into his life perfectly and somehow managed to enjoy the peaceful lifestyle of boring day to day non sorcerer lives.
As much as he loved you he couldn’t help but feel a small tug back towards being a sorcerer. His job was boring, the suffering her saw was relentless, and if he had the power to prevent more suffering from happening why shouldnt he make the change?
But he had to consult with you first. He knew what you would think. He knew you would be scared to lose him just like you both lost haibara.
He walked into their shared apartment looking for his partner with a tired sigh. Tonight he would ask for your advice. And tonight he would choose whatever choice you made