Responses
Age gap: https://www.mangago.zone/home/mangalist/2439656/
Number 2. Manwha, incest
number 12. It's bl manga yes, srry. But i think that's as problematic as it gets
Number 1. age gap ain't wild but relationship is dubious at best
Number 9. This barely enters the list, but for the snowflakes out there
Mofuku no Hanayome, Jawbreaker, and Stigma. These arent really hidden especially stigma and tbh I don't know if they fit what you wanted but I think you would like them if you haven't read them.
I feel like reading some forbidden love AGE GAP (but not old guys, 40’s max) stories with some toxic obsessive relationship traits- smutty with good storylines— hidden gems preferred.
—- no shounen ai —-
Student x teacher
Gangster x innocent
Dad’s friend or older family friend.
Non-blood new family thru marriage.
Rich guy x poor
^*So I have this preference where I only like straight stories when they are Japanese mangas. I don’t really like straight manhwas. So, BL for either one but straight for only mangas*^