I Have Seen Your Paintings and Know Your Handwriting

The first time they met, he asked for her number. Well, maybe she saved his sister and wanted to thank her. Second meeting, what? Why are the love letters he wrote in high school in his study? Well, let's take it away quietly. The third time, she was knocked against the wall, "Gu... Mr. Gu, are you drunk too much?", And the only answer she received was a passionate kiss. The fourth time, she was just accompanying her senior to chase her best friend, but he decisively dragged her to the Civil Affairs Bureau... (The male and female protagonists are clean physically and mentally, 1V1, warm text.)