It's CN -Modern day setting -MC has a son on his former teacher but learns it on later chapters because the woman hides herself from the MC. -It's Harem btw. Thanks.....
How could he have it with his teacher if he didn't know about it until later. He certainly couldn't raise it with her if he didn't know about it.
He’s saying the MC knocked up the teacher but since he didn’t raise the kid it was ‘On the teacher’ not ‘with’.
They fucked and then the women don't tell? I mean the instant someone knocked up someone It mean you have baby with ,subjectively speaking not on someone . If you have baby on someone it mean the baby is on top of s/he? Like riding Maybe If it wrong then it must mean my English is very bad then No offense
On has a lot of meanings more than being on top of, it's one of the longer definitions in dictionaries and complicated so it doesn't mean your English is very bad. https://www.merriam-webster.com/dictionary/on You can use it like "Jeff scored a point on his opponent Steve" in say a tennis match. They are playing together so you can say "Jeff is playing with Steve", but they are opponents.