Imouto Days

One day, as a certain deadbeat 28-year-old host, Yuuta Kikumura, was returning home from work, he noticed an unfamiliar girl sitting in front of his house. It was a 10-year-old Filipino called Diana. Her mother remarried with Yuuta's father and shortly thereafter met with a traffic accident, leaving her stranded at the hospital. Yuuta's father unable to stay home due to his working conditions, results in an apartment left with just a "brother and sister."

Diana and Yuuta, whom are of different generations and speaking different languages, are forced to start living together. How will this go?