At heart, loved girl dancing with you so energetically (10)
I believe the answer is:
vigorously
'energetically' is the definition.
(thesaurus)
'at heart loved girl dancing with you' is the wordplay.
I cannot quite understand how this works, but
'girl' could be 'vi' (short for Violet) and 'vi' is found within the answer.
'you' could be 'u' (homophones) and 'u' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
'so' acts as a link.
Can you help me to learn more?
(Another definition for vigorously that I've seen is " with gusto".)