Time Out says
R.O. Star offer fresh coffee for ¥100 during the day, while their sandwiches and desserts are also both tasty and wallet-friendly. Order a coffee soft serve and find a sunny bench in the nearby park. They also sell a selection of their beans for you to take home; beans can be ground behind the counter too.
1F, 3-2-20 Toyosu, Koto-ku
|Transport:||Toyosu Station (Yurakucho line, Yurikamome), exit 1c|