LoL. What do you mean by that, don't assume something out of the blue like you just crawled out of a rock somewhere. It's a cliché plot, it's been used for so long you didn't even have to guess how far it comes regardless of the artist's origin.
It's not healthy, well some are even worse, but that's why it's called fiction.
They're not supposed to be fine, it shouldn't be normalized as fine, and you should know those are not fine. It's categorized Mature for a reason.
I am 35...I've been reading manga for decades. This has been a thing for ever!
What I mean that it is a cliché plot. A horribly cliché plot. Which is why it actually could be normalized in society because constant media depictions does that. Saying it is fiction doesn't cover it, fiction and media effect our thinking. All cultures have their media trouble spots when it comes to romantic stories. Even generic American romcoms.
Hundreds of otherwise great love stories with the same start. Drunk sex, black out drunk even considering the memory loss.