Teach My Little Sister How To Drive demo goes viral, AI bill hits 7,000 yuan a day as four-person team takes out a loan

The demo of Teach My Little Sister How To Drive, a driving-teaching sim from four-person studio Easy Fox, went viral on Steam and social platforms, with playtest numbers growing more than 20-fold in a month. Because the sister's voice is generated in real time by a cloud large language model, daily AI costs exceed 160,000 yen, about 7,000 yuan, forcing the team to take out a bank loan to keep servers running and to say the demo may be taken down early. The studio says the full release will fold AI costs into its price so buyers pay no extra token fees.