I give my First Love to You

There was a boy named Takuma Kakinouchi. He was treated in a hospital because a heart disease. The doctor told that he just until 20 years age. His family was so shocked. Takuma had a friendship with the daughter Doctor. The name was Mayu Chan. Takuma was very fond Mayu. Mayu was the first love of Takuma. THey were grow up together. They studied in the same school and played together.
One day there was a boy. The named was Kou. Kou loved Mayu. So, he wanted Takuma dissapeared. But, Takuma still loved Mayu so much. Takuma and Kou did a game. The winner must won the race. Finnaly Takuma won the race, so Kou must dissapeared.
Takuma and Mayu must be very happy. They grew up together.
And 20 years of age it was getting close. One day Takuma felt sick in his heart.