Playboy Kou picks up poor Shinobu fresh off of a broken heart and brings their one-night-stand into the workplace when they realize they're president and subordinate. But when Shinobu falls in love, Kou cruelly dumps him and moves onto the next toy. Shinobu realizes their relationship was just a game, accepts a job transfer, and ends personal contact. Kou, who has never been in love, grows distracted and ill. Coming to terms with his feelings, he attempts to confess to a wiser Shinobu, who understandably takes it as part of the game and rejects him, leaving Kou to do what he can to regain Shibou's trust.
REALLY GOOD CHARACTER DEVELOPMENT! Kou is a real jackass, but he learns from his past behavior and becomes a much better version of himself. I was really surprised and pleased to see a story address this. Shinobu used the time to gain confidence in himself. I hope good things for him. And Shinobu's friend Kenji is the sweetest!
Hina wa Mitsuiro no Koi ni Torawareru