Romance manga

It's straight
Fl is like a delinquent, not like fighting and annoying but she just broke the uniform rule and have ear piercing.
Ml is like those going around and giving ppl ticket if they violate a rule, a kaichou some sort.
I dont remember how they date but...when they date they only do innocent stuff since ml family is rich + strict (im not sure here if im confusing this w another manga). If i remember correctly, the last time i read the latest chapter they did beyond(?) Like after a small drinking party in his flat/house, she stayed when everyone left and they boombaya.