
But Wada is not ordinary older people. He is her step father. I know asian call all older people related or not uncle or auntie because i am asian but not on our parent (even if they are our step parent). And usually they also never does that in manga that involve step parent. If they dont call them otosan (dad), they call them oyaji (old man), and usually done only if the character dont really get along with their parent, but uncle? That why this translation confuse me.

Hey there, translator here. Wada is indeed Chiho's step dad. She calls him Ojisan in the Japanese which can mean uncle or just older man in general. I think it can be inferred that Chiho didn't want Wada to become her step-dad which is why she refuses to acknowledge it by calling him what you would call an older person on the street. I hope that clears it up a bit.

I personally think translating it as "old man" would deprive the word the detachment Chiho's feeling towards Wada,because "old man" is still an endearing familial term. As someone who have a step mother that I'm not fond of, who I still call "auntie", I think "uncle" or maybe the plain "ojiisan" would be more befitting, especially if this will become an important plot point in the future!

But for asian, calling your parent something else from dad or mom is kinda like an insult (Step or not). Uncle made it kinda confusing, because like i say, it can mean real uncle or not. Oldman in my opinion still better. A lot of anime character that have rough relationship with their parent call them old man or old hag (For mother). But probably keeping up with Ojisan as word is better in translating the series. They (The translator) usually keep the japanese word for familial or relationship term in Japanese as different word even though translate to english roughly same can have different meaning and connotation in japanese (Like Aniki and Nii-san)
I wonder what Yuneko (Wada wife) would react when she found out that his husband is Hashimoto high school crush (Fujoshi mode turn on?). And i think there is some kind mistranslation here. As far as i remember, Chicho-chan is Wada niece. That why she dont like it when he came instead her mom at parent-student day and she call him her uncle at Chapter 9. But why she call Wada wife Mom? (But i also confuse, because in Chapter 10, Wada say that her wife has gotten divorced one and she bring this child together with her while pointing his finger at Chicho-chan. So i don't really know which part is wrong). If somebody have read the raw, can you confirm which one is right?