regshoe

Surely one would not say 'hampering myself with a shit'.

Okay, I've gone through all the S words in this slang dictionary, and found these insults:

SAUCE BOX. A term of familiar raillery, signifying a bold
or forward person.
SCAB. A worthless man or woman.
SCOUNDREL. A man void of every principle of honour.
SCRUB. A low mean fellow, employed in all sorts of dirty work.
SLAG. A slack-mettled fellow, one not ready to resent an
affront.

The only one that fits the situation is 'sauce box', but I don't know if it really sounds right. Possibly 'scab', but that does seem a bit harsh! 'Slag' is about the opposite of Ewen at that point. : )