I wanted to ask is there any restriction to the story progress if I focus on only one heroine at a time and after completing her entire storyline I move into another heroine?
A few of the love interests will have quests that require interacting (not necessarily sexually) with other love interests in order to progress.
A few more of the love interests have quests/interactions that can be dependent on others (not necessarily a love interest), involving things like unlocking tailoring or even particular sex positions (anal is a common one).
There are also some interwoven quests where if you've progressed one it will affect how another plays out. An example of this without spoiling anything is the interactions between Mira, Frisha and Emily.