Sara2001
If it is partly a punishment,yes,it can be understandable he doesn't want to make it easy or comfortable for her more than necessary.I hope for her he can be a bit more lenient after some time,if she behave well.
Angelina the question cannot be finally clarified but you can clarify it for yourself if you ask yourself if you think that if she had behaved correctly she would not have gotten the bra
If I've understood @Sara2001 correctly,having a boyfriend would mean having to wear a chastity bar,for her,anyway.But she would have been more free at home(when her boyfriend would not be here too,I guess),if she have asked her father to be allowed to have a boyfriend and if he agreed(and approved him).
She dated her boyfriend secretly,without asking for permission,so it is now more strict for her,as a punishment.