Oji-san ga Joshi●sei ni Warui Koto wo Oshieru - Ch. 10

[MangaDex]

 

[Tamerlane]

"Oji-san"/"Oba-san" are indeed honorifics for someone who is substantially older than you and that is close to you. If they're closer in age, you'd use "Onii-san"/"Onee-san." It's like if you're in a job, the person older than you/more experienced by a lot is usually called "sensei" out of respect, and if they're not older than you but have more experience or are around the same age, they're called "senpai."

It's a metaphorical kind of thing more than a literal blood-related association.

 

[bigtiddyoneesan]

It does feel good to touch when it's like that tho

 

[justforthelulz]

Yeah, pretty sure he's always been a not-blood-related companion.

 

[Askorti]

@Tamerlane

I don't think sensei is used outside of some kind of teaching/training/medical/science environment, even when there's a gap in age. You wouldn't call a more experienced laborer sensei. But a researcher, maybe.

 

[IrregularPerson]

thank you for the update. I had some idea it WAS appropriate to call unrelated people brother/sister in China, and I know for a fact in the US uncle/aunt can be used for your parent's friends. but because its a Japanese setting, I haven't seen such use before. most manga usually have a cast of the same age group or otherwise, different ages wouldn't be as affectionate or are actually related (blood or that step-sibling trope).

 

[Willieddd]

@bigtiddyoneesan it does. I 'm always doing it after shaving.

 

[Ke_Zunjian]

No lie, it is satisfying to do that.