Zettai Kekkonsuru Man vs Zettai Kekkonshinai Woman

"Please marry me." Tetsuko is suddenly proposed to by Kosuke, the vice president of a business partner, after they had a one-night stand together. "I can't." Tetsuko, who had no desire to get married, immediately refused. But one after another, Kosuke made friends with her colleagues and acquaintances, as he slowly eroded her defenses....... Until she found herself in an atmosphere of "you have no choice but to get married." How did it come to this? It's true that she liked his face, but what is Kosuke's true intention for coming on to her so hard? (Source: Opal Comics, translated)