Yes! Hibiya is omega. But I don't know Yamagi's beta or alpha 'cause I didn' read all chapter throughly. They have a child called sana though. So, probably Yamagi is alpha?
hibiya is beta initially but after the 'bee' incident, his gene undergoes mutation and he becomes an omega ( well that's what i understood seeing the raw)
Just like when victor enter yuuri's room
http://www.mangago.me/read-manga/shingeki_no_kyojin_dj_fan_service_omegaverse/mi/134564fdae7ac9e3c252fd128335cf8d_chapter-2/16/











Has began!!!
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