Butler
a!Yoo Jekwon x b!Seo Yian (turns omega) To work as a butler, you must be a beta. Seo Yian has happily lived his life working as a butler for the hotel's alpha V VIP Yoo Jeokwon, tending to his every need but when those needs turn sexual after Mr. Yoon catching his partner cheating, things change. Seo Yian, who's harbored a crush on Yoon Jeokwon for years, offers his body up... at the unknown cost of that many alpha pheromones turning him into an omega.
Shingeki no Kyojin dj - Mihitsu no Koi ni Yoru Ai
99.99% Lovers
a!Lee Hwan x o!Kang Haejin Kang Haejin is, for all intents and purposes, a weak omega with no family left to care for him. He accidentally catches the eyes of director Lee Hwan, an alpha who was told by his grandmother that he couldn't take over the company until he had a mate and child. Lee Hwan catches Kang Haejin's scent and manages to run a compatibility test between their DNA, finding a 99.99% rate between them so he begins the seduction of the omega ASAP, despite not liking him at all.
Reversal
a!Kwon Sung-Hyeop (Joo Sung-Hyeop) x o!Lee Ha-jin (Baek Yoo-han) Lee Ha-jin, once known as Baek Yoo-han, was born a recessive omega to a family that wouldn't accept that so he underwent the serious treatment to transition to a beta which is how he now lives. When an opportunity for his company comes up, he meets with Kwon Sung-hyeop who is none other than his old friend, Joo Sung-hyeop. The meeting goes awry when Sung-hyeop admits he only is interested in the company to get close to Ha-jin again.
I Found You, My Omega
Shima-chan Chi no Tsugai Jijou
a!Kuroga Akane x o!Shirosaki Aoi A mated pair retelling their story to their daughter... Punks at rival schools, Kuroga Akane and Shirosaki Aoi end up face to face under a bridge after a little misunderstanding between their schools. As they're beating the shit out of each other, Shirosaki's heat gets triggered and Kuroga reacts as any alpha would until he comes to his senses and punches himself in the face to snap out of it. From there, all because of a cat, they start to hang out and realize they're True Mates.
An Omega's Love Affair
a!Ha Sung-woo x o!Lee Hyun Lee Hyun doesn't want to deal with matchmaking to find a mate, Ha Sung-woo is in the same boat (according to him), so they end up "going out" as a means to fool their families into dropping their attempts at making them find a mate. (more chapters, better quality translation on yaoimangaonline.com)
Lead Heart - Attack on Titan dj
Eruri, Erwin x Levi Omega Levi, a student of alpha Erwin's, finds out he's pregnant with his sensei's baby. Rather than tell Erwin, he avoids him and skips school until Erwin shows up at his apartment and figures it out himself.
Baby, Punk Kid