Boy or girl I love? One may be just outside the house (5)
I believe the answer is:
patio
'one may be just outside the house' is the definition.
'boy or girl i love?' is the wordplay.
'boy or girl' becomes 'pat' (unisex name, Patrick or Patricia).
'love?' becomes 'o' (In tennis, 'love' means 'zero').
'pat'+'i'+'o'='PATIO'
(Other definitions for patio that I've seen before include "Paved eating area adjoining house" , "Barbecue location?" , "area near house" , "Garden terrace" , "Exterior paved area" .)