There’s nothing of the sort in this series, at least as far as the new adaptation goes. I haven’t watched the original anime adaptation nor am I familiar with the source material, though.
The MC doesn’t really have any romantic interests, he’s got other things to focus on.
I agree. I never understood all the jokes about foster siblings either. It’s a sign of little intelligence.
I have no idea what you’re asking. Learn to formulate your questions more accurately, concisely, and clearly. But the things you are discussing are disgusting. Foster children have had to go through some difficult experiences. It is not uncommon for their psyche to become very unstable and fragile after their days. You have no idea how hard it is for these children because you have probably never had any contact with them. Instead, you could visit https://fosterplus.org and read information about these children, about foster families, and the challenges they face. Maybe you will understand what inappropriate words and jokes you allowed yourself to say after visiting Foster Plus. All the best!