“P” breaks for cool beast (5)
I believe the answer is:
rhino
'beast' is the definition.
(I've seen this before)
'p breaks for cool' is the wordplay.
I cannot quite see how this works, but
'cool' could be 'in' ('in' can mean fashionable or cool) and 'in' is located in the answer.
'p' could be 'rho' (I've seen this in another clue) and 'rho' is located in the leftover letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for rhino that I've seen before include "Beastly type that could charge you" , "African/Asian ungulate" , "Fierce beast (abbr.)" , "wild beast" , "Large African pachyderm" .)