You're welcome to stay with me (2,2,5)
I believe the answer is:
be my guest
'you're welcome to' is the definition.
I can't tell whether this definition defines the answer.
'stay with me' is the wordplay.
I cannot quite understand how this works, but
'stay' could be 'be' (stay can mean to continue to be a certain way) and 'be' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for be my guest that I've seen before include "Please do!" , "Help yourself!" , "as 1 [HOTELIERS] might say" , "Do as you wish!" , "Go ahead" .)