I'm thinking you got the idea based off of this one that's been recently updated...
http://www.mangago.zone/read-manga/shingeki_no_kyojin_dj_mihitsu_no_koi_ni_yoru_ai/
I don't see much alpha omega stuff in mangas, but then again I don't read many DJ's (￣∇￣")
Thank you for your help but I already read this manga :( And yes, you're right. I read one of the last updated attack on titan dj and I really loved alpha&omega theme (-:
http://www.mangago.zone/read-manga/shingeki_no_kyojin_dj_love_letter/
This one contains a similar theme!
I am searching for attack on titan dj. Alpha & omega themed. Thanks fot help!