A lecherous host welcomed in glamorous hangers-on (3,5)
I believe the answer is:
arm candy
'glamorous hangers-on' is the definition.
(attractive people hanging off their dates' arms)
'a lecherous host welcomed' is the wordplay.
'lecherous' becomes 'randy' (both can mean sexually aroused).
'host' becomes 'mc' (short for master of ceremonies).
'welcomed' indicates putting letters inside (inserted letters are welcomed in).
'randy' placed around 'mc' is 'rmcandy'.
'a'+'rmcandy'='ARM CANDY'
'in' is the link.
(Other definitions for arm candy that I've seen before include "sexy companion?" , "beautiful girl" .)