Jazz (manga)

Dr. Narusawa gets called into work in the middle of the night to treat an asthma patient, Naoki Segawa. When Narusawa orders out Naoki's demanding and overprotective mother, Naoki takes an immediate liking to Narusawa and asks to transfer under his care until he graduates high school. Although Narusawa keeps his distance from everybody, he sees in Naoki his former self and tries to encourage him while he is still a patient.

Upon Naoki passing his entrance exam he treats Narusawa to dinner, during which he drugs and then rapes him. A month passes by nervously for Narusawa, when suddenly Naoki sends him a ticket to Tokyo to meet him. Both scared of and fascinated by Naoki, Narusawa does go to Tokyo, and ends up forced into a relationship that spans several years and continents as he gradually comes to care for Naoki.

If you're into younger mentally-unbalanced Semes, cold and distant Ukes, Stockholm Syndrome, and doctor/patient relationships, read Jazz.

Tropes used in Jazz (manga) include:

Beta Couple: Cathy and Michael, Takino and Mizushima (who are a Similar Squad to Naoki and Narusawa, mainly differing by being less melodramatic).
Crazy Jealous Guy: Naoki
Emotionless Guy: Dr. Narusawa has a completely empty life before meeting Naoki because he had been raised to think he only had value if he became a doctor, to the exclusion of anything he wanted, making him extremely passive and anti-social.
Heroic BSOD: When Naoki doesn't actually die over Narusawa leaving him like he thinks he should, he falls into one.
Kick the Dog: An absolutely spectacular example (possibly even a Moral Event Horizon) in Volume 2. For their second Christmas together Narusawa decides to buy Naoki a gift to show he loves him, and gets help from his colleague Michael, eventually picking a cologne reminescent of the one Naoki gave him once. Naoki on the other hand is anxious that Narusawa seems not to want to spend Christmas with him, and is still worried that he is just going along with their relationship for the sake of it. When Michael leaves a vague message about their evening together Naoki suspects the worst and works himself into a rage. Soon enough Narusawa arrives home feeling excited about the gift and hopeful about Naoki's reaction. Naoki immediately accuses him of cheating, notices the scent of another person's cologne, and loses it even further, brutally raping Narusawa who doesn't get the chance defend himself. This is followed by anvil-sized My God, What Have I Done? realization when the prone Narusawa calmly tells Naoki to go look in his coat-pocket and he finds his present.
Lonely Rich Kid: Although he can make friends easily, Naoki does act like this in respect to his overbearing parents, which is probably what Narusawa picked up on when he was reminded of himself when he was young.
Opposites Attract
Stepford Smiler: Narusawa since childhood.
Stockholm Syndrome: Narusawa gets used to Naoki's aggressiveness after awhile and eventually falls in love.
There Are No Therapists: Considering Narusawa is a doctor there really should be available therapists but neither he nor Naoki seem to see one in spite of Narusawa's childhood trauma and Naoki's seriously unbalanced behaviour. Their relationship drama is their therapy by the end.
Unequal Pairing: Narusawa is a doctor and Naoki his patient, but Naoki actually holds all the power.