The Boss Is My Sadistic Sweetheart!

I, Haruka Shinozuka, am 27 years old and still a virgin (never had a boyfriend, even). One day, the division chief, Okubo, sees me despairing over being turned down after the confession I had to work up the courage to make. And if that weren't bad enough, he steals my first kiss in the name of "shutting up that pathetic wailing"! Division Chief, who do you think you are? Do you think you can get away with anything just because you're handsome...? But his next words really throw me for a loop: "If you're still single when you turn 28, I'll take you." ...What? Was that just... a proposal?! Division Chief, are you serious?! Before I know it, the two of us are at a hotel, and engaged in some serious premarital relations... (Source: MangaPlaza)