Context. This paper aims to investigate the potential of sustainable interaction system by employing persuasive design process. Sustainable Human Computer Interaction community (HCI) strives to find effective ways to change human behavior toward pro-environment. The sustainable HCI community seems to propose ambient display interface as one of its major interaction methods, which have an impact in quiet and static surroundings. However, when it comes to crowded public places where public resources are heavily wasted, ambient interfaces hardly get people’s attention and provide timely information to people. Goals. The author proposes an embodied sound interface as an alternative in the crowded places. The embodied sound interface serves to alert people at the right moment in a fun and pleasant way to induce people to engage in an intended behavior spontaneously. A sensor system prototype embedding an embodied sound interface, musical hand shaker (MHS), was developed aiming at reducing the use of paper towels. The MHS is placed near the water tap in a restroom and it respond with a music to the hand shaking of the user in front of the MHS. The system encourages people to experience how easy it is to save paper towel and do a green activity in their daily life. Methods. This study is grounded on three HCI fields: ambient information systems, affective interaction, and persuasive technology. The MHS prototype went through the persuasive design process which includes iterative steps of prototype implementation and evaluation. This design process centered on the eight steps of design process and Fogg behavior model. The persuasive qualities of embodied sound interface such as understandability, recognition of the system goal, and persistency of raised awareness of sustainability were examined. Results. The final outdoor evaluation in the restroom of a mall confirmed the impact of the MHS on people’s habit of using paper towels as well as its effectiveness of persuasion. Since it is a pilot study, there remain some unresolved issues and open questions for researcher in HCI and psychology fields.