Son at guesthouse with old queen who's a bit of a rascal (6)
I believe the answer is:
sinner
'a bit of a rascal' is the definition.
I can't judge whether this definition defines the answer.
'son at guesthouse with old queen' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'at' means one lot of letters go next to another.
'guesthouse' becomes 'inn' (I've seen this in another clue).
'with' is a charade indicator (letters next to each other).
'old queen' becomes 'ER' (Elizabeth Regina, ie Queen Elizabeth).
's'+'inn'+'er'='SINNER'
'who's' is the link.
Can you help me to learn more?
(Other definitions for sinner that I've seen before include "One morally corrupt" , "One who breaches the moral law" , "Person straying" , "Wrong-doer" , "One who breaks moral law" .)