Responses
It's common here to address older lovers with honorific 'san' some wives even address their husbands (and sons) their names with -san.especially those who came from a traditional family.
Is it really that strange? I personally think it adds to Jun's cuteness (=・ω・=)
Don't you think it's kind of strange that Jun calls his lover by his 'proper name' (Saki-san) while his lover calls him by his given name? After a year of being together and even living together I would have thought that his older lover would have pushed for that 'next level' but he never even seemed to notice.
And I do wish they would make an anime and a sequel of this! So cute...