Haikyu!! Dj - Ore To Osananajimi No Shoya Ni Matsuwaru Arekore
Oikawa and Iwaizumi are finally dating. Both love each other but at the moment they're in some kind of dilemma: how to go from kissing to sex. Oiwaka is such a fine good boyfriend and he knows better than anyone else what Iwa is thinking so he takes the first step and invites Iwa to spend the weekend at his place. It's lovely how considerate are with each other. I love them.
Haikyu!! - Hikari no Ko (Doujinshi)
For an omega to give birth without being bonded is quite unusual and as a consequence they get badly sick. That's the reason why Oikawa left Iwaizumi and his child and went overseas for years, to go under treatment but now his daughter doesn't recognise him as a mother now that he is back.
Haikyu!! - Higan no Kagee (Doujinshi)
After highschool, the four third years go to Tokyo and live as roommates during his college years. During that time, Iwaizumi and Oikawa start a relationship and they're deeply in love.
Haikyu!! Dj - Renshuu Jiai No Ato Wa Kanarazu Sex Shitaku Naru