Mayuki and I joined the company at the same time. She has been steadily promoted while I have remained stagnant. Fortunately, despite my lack of career progress, I was able to get married. Recently, work has been overwhelming; last night I couldn't go home and had to work overnight at the company, and of course, I haven’t showered yet. Today, I hope to finish before the last train to go home with my wife. Since this is Mayuki's project, she also came to help me complete it. But she finished while I was still struggling, and by the time I completed my tasks, I had already missed the last train. 'Looks like I won't get to shower again today,' 'You didn't even shower?!', 'You smell so bad!', 'My house is nearby. Come over and take a shower at my place.' Since I smelled so bad, I had no choice but to go to Mayuki's house to shower. On the way, we chatted happily together; having joined the company at the same time, we became pretty close. When we arrived at her house, Mayuki changed into a rather 'revealing' outfit. The shorts exposed the big buttocks, and the top of the massive breasts kept provoking in front of me. My little boy quickly swelled. "Just today..." I couldn't seem to believe my ears. She agreed to let me have sex to my heart's content tonight! And we immediately rushed into each other, constantly having sex all night until the next morning, still working one more round before going to work. Although I wanted to, I didn't dare to ask for it. But when I saw her give me more documents so that I had to work overtime, I knew that our relationship would still be able to continue...