Although I am confused as to what it means to "make five main summary" for the book, I am happy to provide a summary with at least five plot points for you.
Desperaux is a mouse who is born and immediately considered different because he is tiny, has big ears, and eyes that are already open and looking around. From the beginning, Desperaux doesn't do the things a mouse would normally do. In fact, Desperaux is a big fan of reading, especially when it has to do with the princess and the knight.
One evening when Desperaux hears music, he discovers the king performing for his daughter who is named Princess Pea. Desperaux vows to reenact his favorite story, falls in love with Princess Pea, and wants to be her knight. As a result of his goals, Desperaux is banished to the dungeon and forced to see the council because he is so unlike other mice. While there, Desperaux finds that Princess Pea is in danger. Even after he is released, Desperaux goes back to the dungeon in order to rescue his love. Desperaux succeeds in saving her and regains his place with the mice and a permanent place beside Princess Pea as her protector.
“Desperaux," she said. He saw his name on her lips. "I honor you," whispered Desperaux. "I honor you.”