Royal Host - a cozy environment
My all-time favorite family restaurant is Royal Host, a family restaurant that is more upper-class than others. My family usually go there just to relax, because the have comfortable booth seats. They also have a drink bar and therefore it's a great place to hang out and talk with your friends!
My favorite item on the menu is the onion-gratin soup. As a child, I ate the onion-gratin soup whenever I was sick or had a sore throat. The onion just melts in your mouth and the soup is full of flavor.
A great place to just spend time and relax, especially during the extreme months when it's either too hot or cold to stay outside. They are everywhere around Tokyo and Japan, so a simple search for "Royal Host" would get you to this family restaurant!