Kurogane's Things

I don't really remember anything apart from the fact that it was about former yakuzas becoming idols to pay for their debts. PLEASE HELP

So I read a couple a shojos at the beggining of the month but forgot the names and now I cant find them. Can someone help me?
One is about a girl and a boy called Suzuki i think that like yakuza movies and go to a really famous school. The bullying in the school was awful so both of them decided to change so they could make the school better.
And the second is about a girl who lost her memory in a accident, and she founds she was sort of a bitch before, so she tries to change. Also she had a crush on he brother but I dont remember if they were related? She had a little sister that hated her as well.
Um, if someone know about any of this mangas it will be a big help!

Hi, hello! I would like to make new friends! I am a 20 years old reader who enjoys manga, books and comics and I really would like to make a group chat for people who likes the same things. So if you are interested, please answer.
My ID is siuil