After his beloved grandfather passes away, college freshman Daisuke Ohtaka heads off to begin his college life a few days later than planned. He only got into Torioka University thanks to his grandfather, and now he's lost all his motivation. Then, when he reaches the station, he sees the tiny baseball club leader named Suzume Morino holding up a card with his name on it. His nickname is 'Tweetie!' After getting half-forced into the baseball club, he also has to live under the same roof as Tweetie. The devilish Tweetie has got some big things planned!!