Premika or Premikaa (प्रेमिका) is a Hindi word which can actually be used for 'lover' or 'beloved', as per the context. It comes from Hindi word 'prem' which means love, and a guy who loves someone is called a 'premi.' At the same time, the girl who may just be a beloved can also be called premikaa, though the word is more often used for someone who is in love as well, and is a lover.
So in essence, premika is mostly 'lover,' but can be used for 'beloved' at times.