Loafer in crimson I raised, heel finally slipped into it (5)
I believe the answer is:
idler
'loafer' is the definition.
(I know that loafer can be written as idler)
'crimson i raised heel finally slipped into it' is the wordplay.
'crimson i raised heel' becomes 'iler' (I can't explain this - if you can you should give a lot more credence to this answer).
'finally' says to take the final letters.
'into it' means one lot of letters goes inside another.
The final letter of 'slipped' is 'd'.
'iler' enclosing 'd' is 'IDLER'.
'in' is the link.
Can you help me to learn more?
(Other definitions for idler that I've seen before include "Lazy person" , "A lazy loafer" , "Time waster" , "Someone unemployed" , "One who loafs about" .)