> {}{} {} ****
is a colloquial expression meaning " ** _to wander around idly_** ", " ** _to act in a highly unproductive manner_** ", etc.
It is in the "famous" verb pattern **onomatopoeia + ** .
> **_"What the heck! A big man (= grown man) drinking like a fish and wandering around idly under the broad daylight!"_**
The entire line is in the quintessential Kanto masculine colloquial speech.
Note it is (pi), not .