Looking for this manga

Okay so I don't remember the title of the book, but it's about a girl who pretends to be her brother and goes to a really good school anf she is asked to join this club where it's all filled with boys that have joined the club because they all had past lives that all connected together and later she has a vague memory of being part of the group from the old ages and also later in the story this guy who doesn't really think she should be part of the club, cuts his hair in front of his mom who thought keeping his hair long was good luck or something and the girl was there to watch it when he cut his hair. Please help me find it! Thank you!