Gunjou Other Half

Gunjou Other Half summary:

"I found you, my fated person"
I thought it was something that existed in a totally different universe from mine...
Naganuki Natsume is unexpectedly assessed to have transitioned into an Omega. Unable to catch a break, on that same day, he meets his "fated pair", Arima Kouta.
The naive and innocent Arima, who transferred into his school, remains undettered and constantly whispers his love to Naganuki.
Naganuki had spent his life peacefully until now, but before he knows it, he's already swept up by Arima's enthusiasm...?!
An Infatuated, Devoted Puppy Alpha x An Aloof, Strong-willed Tsun Omega
The two's fates intertwine in this youthful omegaverse school-life story!!