A Lying Omega's Guide to Getting Bitten

Asahi Narumiya can't stand his colleague, Itsuki Tsukishima. Before the latter was transferred to the company, Narumiya was top in sales. Now, Tsukishima is taking over his hard-earned spot. While Narumiya acknowledges Tsukishima's talents, he can't bring himself to like him as a person. When Narumiya forgets his phone once, he returns to the office to find Tsukishima in heat, bringing to light that Tsukishima isn't alpha like he stated on his resume but an omega. In exchange for Narumiya's silence, Tsukishima offers the former to have his way with him and even offers Narumiya to bite him. While Narumiya indulged in having sex with Tsukishima, biting him was out of the question. He hates him, after all. And so begins their complicated relationship. (Source: futekiya) Note: Contains an extra chapter.