It is the topmost command on the right screen. You pick your daily schedule here for both Skip and Real Time Mode.
The icon will change to "Sleep" (寝る) at night in Skip Mode. You choose it to end your day.
In Real Time Mode, the icon will change to "Go to a Date" (デートへ行く) if you have a date scheduled around that time. (It usually changes 20 minutes before the date). If you click it, you will start your date.