Firstly, I would like to correct what user Kin883 has wrote.
It has eight chapters plus special chapter and two mini bonuses scenes.
There is two scenes where Yuu (omega) was almost raped.
First time,
he was attacked by the manager of the swimming club, when he started to emit pheromones because of the thoughts of Ichiya. He was almost penetrated and half-bitten, but he pushed away the attacker, calling Ichiya, so the attacker fell to the swimming pool, and that was the moment when Ichiya came back.
Second time
it was when Yuu got a proposition to attend to gang rape some female omegas, but he rejected it, so this yakuza guy (can't remember his name) made him suck his penis instead, so he knew Yuu was an omega thanks to that Yuu ran away, trying to cover his nape. There was nothing more than blow job, but even Yuu said to him that he almost raped him. In both times Yuu thought about Ichiya and that gave him strength to fight. He never wanted it with someone other than him.
Overall, manga is so-so. I've read better ones, but there were worst too, so if someone is immune to tropes typical to omegaverse stories he can read it.
The only thing I didn't like was that at the end,
when Yuu and Ichiya are reunited, there is no telling about how Yuu was able to live with his body, when after he met Ichiya he started to emit pheromones much stronger that before and even biting his nape hasn't work for that. I mean, other alphas can still feel his smell, so how did he functioned during his heats?! I hope he hasn't had sex with someone else, but I don't think he did, as he didn't want to do this even before they became a pair. Personally, I think that being far away from Ichiya made Yuu's heat less serious, so he could live his life in peace, especially as for sure his workplace was accustomed to work with omegas (other omegas worked there too). Maybe medicine worked correctly, and I thing this is the case, because as soon as Yuu saw Ichiya with other people he got his heat, his body wanted to claim what's his I guess.
The ending could be better, and I wish I could see Yuu when Ichiya told him he doesn't want to have long-distance relationship, but he wants to be with him all the time, but well, I got what I got.
One more thing, for those who asks why Yuu wasn't marked when
club manager bit him, even though Yuu was basically in heat I think it was because in some omegaverse variations there is a rule that omega can only be marked by his fated alpha, mark from any other alpha will just disappear or won't be any mark at all. Besides, there was no semen, and I think that is has to be in order to mark omega.
I felt somewhat anxiety when I read it, because it had to many characters thrown in just one volume, and the ending was too short. I felt like the author made Yuu's heats unstable just to made him resign from school, even though it it made so much questions we get no answers at.