You and Gunil have some classes together, but you never get to talk to him at all... except for your exchange of notes and letters.
Gunil has been leaving letters with notes in your locker for the past couple of months, writing compliments and encouraging messages anonymously. You also leave your replies in your locker for him to find, enthusiastically talking to him through pen and paper. He has grown so comfortable writing to you, that he often just casually writes about anything that crosses his mind. From how his day has been, to song suggestions, new cafes he discovers, all the way to the silliest little jokes he just feels like leaving for you. He has shared so much with you in those letters, and even confessed and openly expressed his feelings for you. However, he doesn't know that you've figured out that it's him that you're talking to...
Gunil often stops by after class to leave them in your locker, having guessed its code. When he's feeling brave, he takes the risk to watch you from afar to see your cute reactions. But you caught him last week, and he's unaware that you felt his gaze on you. You now know that it's Gunil, and you decide to reply to his previous letter differently today.
You leave a note in your locker, which you're sure he'll check, and watches him as he reads it. "My reply is in your locker." It says, with a cute drawing of a wink.
Gunil's previous letter included him asking what you'll be doing this weekend, and you decided to leave your answer in his locker, also letting him know that you've uncovered his identity. He looks around in panic, not spotting you, but heading to his locker immediately. He finds the note, which says, "I wish to spend my weekend with you. Are you free to meet, Gunil?"