Wind Breaker Chapter 203 shatters every assumption about Haruka Sakura. This is the first time we have ever heard him talk. And when he finally does talk, it’s way more powerful than any punches that we've seen so far in the series.
Sakura reveals to Momijikawa what he means by “darkness versus daylight.” Sakura describes how nighttime has always been his escape from the hatred and judgment that come with the stares of cruel people throughout the day. His father has told him he is a murderer and left him at an orphanage, which makes fighting the only form of communication he has for survival.
Sakura Opens Up About His Dark Past

Wind Breaker Chapter 203 takes place with Sakura revealing Momijikawa's backstory. In it, Sakura tells him about how she liked being at Night instead of Daytime because when it was dark, he would not be judged for his appearance (the fact that it is unique in both hair colour and Eye Colour).
When the sun would rise, he would then have to face the world and everyone around him, who would ridicule and hate him for merely existing because he is different.
The chapter also reveals a shocking truth about Sakura's family. When they first met, his father called him a "killer." It crushed any obstacle remaining between Sakura and finding a home.
When Sakura's father left him at an orphanage, he had to rely on being alone. While he was waiting for it to be nighttime, he prayed that the moon and stars would hide his pain from everyone around him.
Finding Strength Through Fighting

Wind Breaker chapter 203 focuses on Sakura's evolution. Upon entering a new school, he encountered a new emotion: hostilities. A moment when he was bullied caused a reaction from deep within himself, and he was able to retaliate because of the pent-up rage he had collected throughout the years of being bullied.
Due to all the anguish he had experienced, he came to realize that through his strength, he could prevent another beating, and fighting was the answer to the years of feeling helpless and in pain.
Sakura's reasons for joining Furin are revealed in this chapter. When he heard the rumors about the school, he thought it was full of delinquents and losers. However, when he arrived, he found out differently.
Furin is where Sakura truly belongs and has made it his home, as shown in the chapter. There, he was accepted by everyone without any kind of prejudice, and they gave him back what he thought he would never have again.
Sakura's Declaration in Wind Breaker Chapter 203

In a fit of rage, Momijikawa seized Sakura by his collar. It disturbed him to see Sakura smiling while talking about a traumatic experience. After Momijikawa heard the entire story, he let go of Sakura and said he was sorry.
Through this exchange, it can be seen how the events of Wind Breaker chapter 203 affect the characters around him. The information regarding Sakura's past has an impact on all who find out about it, and he has earned the respect of everyone due to the strength he shows in overcoming his trauma.
Wind Breaker Chapter 203 ends with Sakura refusing to leave. No matter what anyone says, he won't abandon the place that finally gave him a home. It was the first time he felt at home somewhere, so he will always protect that. Therefore, he cannot be persuaded to leave this place. All he can do is keep fighting against the forces trying to take him from there.
Wind Breaker Chapter 203 is one of the most emotionally impactful chapters within the entire series: Sakura's past has been explained very clearly why he fights the way he does. When you combine that with his fight for his life, it makes an already compelling protagonist much more compelling than he was.