''The Demian Syndrome'' is a BoysLove Manga by Oki Mamiya.

Azuma and Takayama used to be really close friends as children, until one day Takayama disappears to the USA without telling Azuma. Unable to forget about Azuma, Takayama returns years later and enrolls in Azuma's school. He finds his old friend cold and unwilling to restart any kind of relationship... but why? Takayama is a light hearted, happy guy who gets along with everyone around, even though Azuma's odd behavior hurts him. Azuma is cool and distant, and seems not to care about anything around him...

!!This work provides examples of:

* TheAce: Azuma, but his issues make him a BrokenAce.
* ArcSymbol: The Sparrowhawk drawing.
* BatmanGambit: Takayama volunteered to coordinate his cohort's festival activities (and consequently got himself into trouble) to get Azuma to stay around him. It works like clockwork. Several people such as Kurachi have worked it out that if Takayama is involved, Azuma will show up.
* BridalCarry: Azuma carries Takayama like this in Chapter 2 after the latter injured himself in a soccer game.
* CastFullOfPrettyBoys
* ChildhoodFriendRomance: Azuma and Takayama knew each other since they were kids.
* DisappearedDad: Azuma's biological dad.
* EvenTheGuysWantHim: Both leads.
* FieryRedHead: Kurachi
* [[IceQueen Ice King]]: Azuma. Tasuku before Shiba [[DefrostingTheIceQueen intervened]]
* [[IllGirl Ill Boy]]: Takayama when he was younger.
* UsefulNotes/JapaneseChristian: Jouhoku is a Christian school.
* JerkassFacade: Azuma towards Takayama. Still it does not take long for people to figure out that Takayama is ''very'' special to him.
* MissingMom: Takayama's mom
* OverTheShoulderCarry: Azuma has carried Takayama like this at least twice.
* UsedToBeASweetKid: Azuma was much nicer and more open to people before Takayama moved away.
* WillTheyOrWontThey: The series.