Perhaps because he was raised in a single-parent household, Ken has poor social skills and always plays alone. His mother, Keiko, has always been worried about Ken's shy personality and his inability to make friends. One day, however, Ken brought home a friend for the first time. Overjoyed by this unprecedented event, Keiko couldn't hide her happiness... On the other hand, Yuji, the friend Ken brought home, was so shocked by Keiko's beauty that he was on the verge of losing his rationality...
