If she show her real ability it will make king know her ability and end up being used as the ingredient of the imperial living sword. To destroy the kingdom she can let her enemy know her ability
I got feelings princess is not actualy the real princess, she probably using magic to turn into ravi. Fearing that ravi magic is stonger than her , the princess locked her up and later turn her into monster
The spirit is ML and its sucks, cause he kept her caged in her own world...
To be honest what kind of ML is this..
Separate daughter and father like that
Its more friendship here than reverse harem. Its probably because the male protagonist not developing enough intimate feelings towards her(except for the fiancee?)