Time Operation

I'm now working on entertainment computing. So I often think of systems, applications, services and so on that make people pleased, surprised, laugh, and comforted. I really like to think of such entertainment computing. I have a lot of ideas for entertainment computing. Today, I'd like to write about one of them. It's an idea to operate time virtually.
Before I write about my idea of virtual time operation, I have a question for you. Have you ever felt about time as follows; time flies so fast when you do your favorite things and time flies so late when you do your disliked ones? I definitely assert that you have experienced such a feeling. In fact, I have also experienced such a feeling many times before. My idea of virtual time operation is based on this feeling about time.
The basic idea is to change the speed of time. As you know well, the speed of time is always constant. For example, one hour when you work is equal to one hour when you play. Needless to say, the speed in both of them is the same. My basic idea is to change the progression speed of time. For instance, when you work, the speed of time becomes fast and when you play, the speed of time becomes late. Of course, we can't change physical time. But we can change the speed of time in watch and/or clock applications. Concretely speaking, I will implement such a unique watch and/or clock application. By using this application, you feel so good even if you do disliked work or something. Because you feel the time flies so fast.
Before you use this application, you must specify your favorite things and disliked ones and the speed of time progression. You may push a toggle switch when you do your favorite or disliked things, or you may judge your situation by AI depending on the time, date, place, and so on. One of the important things is that the time is adjusted while you sleep in bed. How about this idea? Do you want to use this application for virtual time operation? I don't think that it's so hard to implement this application.