More sentimental wimp must get support (7)

I believe the answer is:

soppier

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'more sentimental' is the definition.
Both the definition and answer are comparative adjectives. Maybe they are linked in a way I don't understand?

'wimp must get support' is the wordplay.
'wimp' becomes 'sop' (I am not sure about this - if you are sure you should believe this answer much more).
'must get' means one lot of letters go next to another.
'support' becomes 'pier' (type of structure).
'sop'+'pier'='SOPPIER'

Can you help me to learn more?

I've seen this clue in The Independent.

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