This girl in our class is CRAZY

his really happened in our class which is kinda mean but CRAZY. There is a boy in our class, and I think about 3 or 4 girls has a crush on him because they don't tell anyone, but you know how some kids act when they like anyone. Anyways, there is a really pretty girl in our class, and she's really cute and kinda flirts with boys, but still acting kind. Then, one of my friend in the group I'm in told me that she also likes that boy. However, today she told me that the girl who flirts with boys had asked that boy "You like me, right?" and the boy answered YES and they were going to start dating from today!! I don't think dating from an young age is a big, serious problem, but the thing is that on the first semester, she liked another boy and that boy dating on the same time, and she said that she's going to trash? throw away?(in korean) that first semester boy which we don't know if he even liked her. Also, it's kinda weird to say "You like me, right?",, not "I think I like you". Plus, she hadn't confess it for an year, but last week, she found out that the girl in our group also has a crush on the same boy. I may be the only one feeling weird about it, but now I think she is not that innocent I thought she would be months ago on the first day of 5th grade. WHY ARE THOSE GIRLS FLIRTING WITH BOYS?? I don't get it, seriously. Thanks for reading, and bye:)