In fact, in this story, the male protagonist never knew that he was the male protagonist. He just happened to sit next to her, happened to be gentle to everyone, and happened to let her walk a long way alone. From being last in the rocket class to being in the top 20 in grade, from being unable to take my eyes away when seeing him to being able to calmly send out blessings after receiving his wedding invitation.
Some people spend their entire youth falling in love with someone, but when they mention it again, they just smile and say, "I just once liked such a good boy."
Purpose: The protagonist in life is always oneself in the end