THAT. IS. A. CLASSIC!

Tell me you’re not thinking of this ;)

Doujinshi Title: Invincible Rhythm

Author: BubunHanten (KAZUKI Rai)

Summary: Hinata asks Kageyama to help him calm his nerves by letting Hinata listen to the sound of Kageyama’s heartbeat. However, this soon escalates into more and more intimate contact, until Kageyama is certain that if he doesn’t stop this right away, Hinata is going to realize that his feelings have escalated beyond that of teammates.

Fandom: Haikyuu!! 

Pairing: Kageyama Tobio x Hinata Shouyou

Language: English

Doujinshi Title: The Story of When I Got Dizzy Author: Bubunhanten Summary: Kageyama and Hinata compete compulsively to see who can stay in the bath the longest, and Hinata quickly realizes he’s made a huge mistake Fandom: Haikyuu!!  Pairing: Kageyama Tobio x Hinata Shouyou Language: English

Doujinshi Title: The Interval of Quest Author: Wrong Direction Summary: Knight!Kageyama abandons King!Oikawa to fight for freedom alongside Hinata Fandom: Haikyuu!!  Pairing: Kageyama Tobio x Hinata Shouyou Language: English

Doujinshi Title: Flavor! Author: Bubunhanten Summary: Hinata borrows Kageyama’s jacket after he spills water all over his own. When he returns it, Kageyama discovers a small gift in the pocket that carries a heavy message. Fandom: Haikyuu!!  Pairing: Kageyama Tobio x Hinata Shouyou Language: English

Hh my god, I know which one you’re thinking of, but I haven’t seen that one in English yet, sadly. To tide you over, here’s a doujin where Tobio turns into a kid for a bit, and Hinata takes good care of him like the amazing big brother he is!

I’m scratching my head on this one.

Two doujins come to mind that take place in middle school after KageHina meet, but those don’t have the scenario you’re describing with Oikawa. 

https://myreadingmanga.info/baked-berry-imaico-haikyuu-dj-cross-restart-eng/

https://myreadingmanga.info/kingyohime-yukijirushi-haikyuu-dj-bounds-eng/

There’s a chance you’re thinking of this dj, where there is a scene that Hinata shows up to hit Kag’s tosses, but only Kindaichi and Kunimi are there for that. 

https://myreadingmanga.info/bubunhanten-little-crow-haikyuu-dj-eng/

Doujinshi Title: Unmei nante iranai Author: Bubunhanten Summary: Hinata admits to the team that he’s an omega, and everyone figures it should be fine since they’re all betas—but then Kageyama says he’s an alpha. Fandom: Haikyuu!!  Rating: R18 Pairing: Kageyama Tobio x Hinata Shouyou Language: English